import time
import requests

POLL_INTERVAL = 5 # in seconds

def start_polling(url):
    while True:
        response = requests.get(url)
        if response.status_code == 200:
            print("Received data:", response.text)
        else:
            print("Failed to retrieve data, status code:", response.status_code)
        time.sleep(POLL_INTERVAL)

if __name__ == "__main__":
    start_polling("http://www.example.com/data")

import asyncio
import websockets

async def echo(websocket, path):
    async for message in websocket:
        await websocket.send(message)

start_server = websockets.serve(echo, "localhost", 8765)

asyncio.get_event_loop().run_until_complete(start_server)
asyncio.get_event_loop().run_forever()

# Sessions Service
class SessionsService:
    def __init__(self):
        self.sessions = {}

    def add_session(self, user_id, session):
        self.sessions[user_id] = session

    def remove_session(self, user_id):
        if user_id in self.sessions:
            del self.sessions[user_id]

    def get_session(self, user_id):
        return self.sessions.get(user_id)

# Notification Service
class NotificationService:
    def __init__(self):
        self.notifications = {}

    def add_notification(self, user_id, notification):
        if user_id in self.notifications:
            self.notifications[user_id].append(notification)
        else:
            self.notifications[user_id] = [notification]

    def remove_notification(self, user_id, notification):
        if user_id in self.notifications:
            self.notifications[user_id].remove(notification)

    def get_notifications(self, user_id):
        return self.notifications.get(user_id, [])

# Chat Service
class ChatService:
    def __init__(self):
        self.chats = {}

    def add_message(self, chat_id, message):
        if chat_id in self.chats:
            self.chats[chat_id].append(message)
        else:
            self.chats[chat_id] = [message]

    def get_messages(self, chat_id):
        return self.chats.get(chat_id, [])

# Message Queue Service
class MessageQueueService:
    def __init__(self):
        self.queue = []

    def add_message(self, message):
        self.queue.append(message)

    def remove_message(self, message):
        self.queue.remove(message)

    def get_messages(self):
        return self.queue

# Last Seen Service
class LastSeenService:
    def __init__(self):
        self.last_seen = {}

    def update_last_seen(self, user_id, timestamp):
        self.last_seen[user_id] = timestamp

    def get_last_seen(self, user_id):
        return self.last_seen.get(user_id)

# Profile Service
class ProfileService:
    def __init__(self):
        self.profiles = {}

    def add_profile(self, user_id, profile):
        self.profiles[user_id] = profile

    def update_profile(self, user_id, profile):
        if user_id in self.profiles:
            self.profiles[user_id].update(profile)

    def get_profile(self, user_id):
        return self.profiles.get(user_id)

import java.util.*;

class User {
    private String username;
    private List<Message> messages;
    private List<GroupChat> groupChats;

    public User(String username) {
        this.username = username;
        this.messages = new ArrayList<>();
        this.groupChats = new ArrayList<>();
    }

    public String getUsername() {
        return username;
    }

    public List<Message> getMessages() {
        return messages;
    }

    public List<GroupChat> getGroupChats() {
        return groupChats;
    }

    public void sendMessage(User recipient, String content) {
        Message message = new Message(this, recipient, content);
        messages.add(message);
        recipient.receiveMessage(message);
        System.out.println("Message sent from '" + username + "' to '" + recipient.getUsername() + "'.");
    }

    public void createGroupChat(String groupName, List<User> members) {
        GroupChat groupChat = new GroupChat(groupName, this, members);
        groupChats.add(groupChat);
        System.out.println("Group chat '" + groupName + "' created successfully.");
    }

    public void receiveMessage(Message message) {
        messages.add(message);
        System.out.println("Message received from '" + message.getSender().getUsername() + "'.");
    }
}

class Message {
    private User sender;
    private User recipient;
    private String content;

    public Message(User sender, User recipient, String content) {
        this.sender = sender;
        this.recipient = recipient;
        this.content = content;
    }

    public User getSender() {
        return sender;
    }

    public User getRecipient() {
        return recipient;
    }

    public String getContent() {
        return content;
    }
}

class GroupChat {
    private String groupName;
    private User creator;
    private List<User> members;

    public GroupChat(String groupName, User creator, List<User> members) {
        this.groupName = groupName;
        this.creator = creator;
        this.members = members;
    }

    public String getGroupName() {
        return groupName;
    }

    public User getCreator() {
        return creator;
    }

    public List<User> getMembers() {
        return members;
    }
}

class WhatsAppSystem {
    private Map<String, User> users;

    public WhatsAppSystem() {
        this.users = new HashMap<>();
    }

    public void registerUser(String username) {
        if (!users.containsKey(username)) {
            User newUser = new User(username);
            users.put(username, newUser);
            System.out.println("User '" + username + "' registered successfully.");
        } else {
            System.out.println("Username '" + username + "' is already taken.");
        }
    }

    public User getUser(String username) {
        return users.get(username);
    }
}

public class WhatsAppApp {
    public static void main(String[] args) {
        WhatsAppSystem whatsapp = new WhatsAppSystem();

        // Register users
        whatsapp.registerUser("user1");
        whatsapp.registerUser("user2");
        whatsapp.registerUser("user3");

        // Send messages
        User user1 = whatsapp.getUser("user1");
        User user2 = whatsapp.getUser("user2");
        user1.sendMessage(user2, "Hello, how are you?");

        // Create group chat
        User user3 = whatsapp.getUser("user3");
        List<User> members = new ArrayList<>();
        members.add(user1);
        members.add(user2);
        members.add(user3);
        user1.createGroupChat("Family Chat", members);
    }
}

from flask import Flask, request, jsonify

app = Flask(__name__)

# User Service API
@app.route('/users', methods=['POST'])
def create_user():
    # create a new user and return user ID
    # actual implementation may involve authentication and user management
    return jsonify({'user_id': 'user123'})

@app.route('/users/<user_id>', methods=['GET'])
def get_user_profile(user_id):
    # return the profile information for the specified user ID
    # actual implementation may involve retrieving profile information from a database
    return jsonify({'user_id': user_id, 'name': 'John Doe', 'phone_number': '1234567890'})

@app.route('/users/<user_id>', methods=['PUT'])
def update_user_profile(user_id):
    # update the profile information for the specified user ID
    # actual implementation may involve authentication and database updates
    return jsonify({'user_id': user_id, 'name': 'John Doe', 'phone_number': '1234567890'})

# Chat Service API
@app.route('/chats', methods=['POST'])
def create_chat():
    # create a new chat and return chat ID
    # actual implementation may involve database updates and user management
    return jsonify({'chat_id': 'chat123'})

@app.route('/chats/<chat_id>/messages', methods=['POST'])
def send_message(chat_id):
    # send a new message to the specified chat and return message ID
    # actual implementation may involve authentication, database updates, and message delivery
    return jsonify({'message_id': 'message123'})

@app.route('/chats/<chat_id>/messages', methods=['GET'])
def get_messages(chat_id):
    # retrieve messages for the specified chat
    # actual implementation may involve retrieving messages from a database
    return jsonify({'chat_id': chat_id, 'messages': [{'message_id': 'message123', 'sender_id': 'user123', 'content': 'Hello World', 'timestamp': '2023-02-19T10:15:00Z'}]})

# Group Service API
@app.route('/groups', methods=['POST'])
def create_group():
    # create a new group and return group ID
    # actual implementation may involve database updates and user management
    return jsonify({'group_id': 'group123'})

@app.route('/groups/<group_id>/members', methods=['POST'])
def add_member(group_id):
    # add a new member to the specified group and return member ID
    # actual implementation may involve authentication, database updates, and user management
    return jsonify({'member_id': 'user456'})

@app.route('/groups/<group_id>/members', methods=['GET'])
def get_members(group_id):
    # retrieve members of the specified group
    # actual implementation may involve retrieving member information from a database
    return jsonify({'group_id': group_id, 'members': [{'user_id': 'user123', 'name': 'John Doe'}, {'user_id': 'user456', 'name': 'Jane Doe'}]})

if __name__ == '__main__':
    app.run(debug=True)

from flask import Flask, request

app = Flask(__name__)

users = {}

@app.route('/send_message', methods=['POST'])
def send_message():
    sender = request.form.get('sender')
    recipient = request.form.get('recipient')
    message = request.form.get('message')

    if recipient in users:
        users[recipient].append((sender, message))
        return 'Message sent successfully!'
    else:
        return 'Error: recipient not found'

@app.route('/get_messages/<username>')
def get_messages(username):
    if username in users:
        messages = users[username]
        users[username] = []
        return str(messages)
    else:
        return 'Error: user not found'

if __name__ == '__main__':
    app.run()

import json
import uuid

class User:
    def __init__(self, name, status='offline'):
        self.name = name
        self.status = status
        self.id = str(uuid.uuid4())

    def __str__(self):
        return f'{self.name} ({self.status})'

class Message:
    def __init__(self, sender, content, type='text'):
        self.sender = sender
        self.content = content
        self.type = type

class Chat:
    def __init__(self, name, users=None):
        self.name = name
        self.users = users or []
        self.messages = []

    def add_user(self, user):
        self.users.append(user)

    def add_message(self, message):
        self.messages.append(message)

class WhatsApp:
    def __init__(self):
        self.users = {}
        self.chats = {}

    def create_user(self, name):
        user = User(name)
        self.users[user.id] = user
        return user

    def create_group(self, name, users=None):
        chat = Chat(name, users)
        self.chats[chat.name] = chat
        return chat

    def send_message(self, chat_name, sender, content, type='text'):
        chat = self.chats.get(chat_name)
        if chat:
            message = Message(sender, content, type)
            chat.add_message(message)
            for user in chat.users:
                if user.status == 'online':
                    print(f'Notification sent to {user.name}: {sender.name} sent a new message in {chat.name}')
        else:
            print(f'Chat {chat_name} does not exist')

    def update_user_status(self, user, status):
        user.status = status
        print(f'{user.name} status updated to {status}')

    def serialize(self):
        serialized = {
            'users': {user.id: {'name': user.name, 'status': user.status} for user in self.users.values()},
            'chats': {
                chat_name: {
                    'name': chat.name,
                    'users': [user.id for user in chat.users],
                    'messages': [
                        {'sender': message.sender.id, 'content': message.content, 'type': message.type}
                        for message in chat.messages
                    ]
                } for chat_name, chat in self.chats.items()
            }
        }
        return json.dumps(serialized, indent=2)

whatsapp = WhatsApp()

class User:
    def __init__(self, username, password):
        self.username = username
        self.password = password
        self.contacts = []
        self.privacy_settings = {}

    def add_contact(self, contact):
        self.contacts.append(contact)

    def update_privacy_settings(self, settings):
        self.privacy_settings.update(settings)

    def authenticate(self, username, password):
        return self.username == username and self.password == password

# Example usage
user1 = User("john", "password123")
user2 = User("alice", "password456")

user1.add_contact(user2)
user1.update_privacy_settings({"show_online_status": False})

authenticated = user1.authenticate("john", "password123")
print(authenticated)  # True

from queue import Queue

class MessageQueue:
    def __init__(self):
        self.queue = Queue()

    def enqueue_message(self, message):
        self.queue.put(message)

    def dequeue_message(self):
        return self.queue.get()

class MessageRouter:
    def __init__(self):
        self.routes = {}

    def add_route(self, recipient, queue):
        self.routes[recipient] = queue

    def route_message(self, message, recipient):
        if recipient in self.routes:
            queue = self.routes[recipient]
            queue.enqueue_message(message)

# Example usage
message_queue = MessageQueue()
alice_queue = MessageQueue()
bob_queue = MessageQueue()

message_router = MessageRouter()
message_router.add_route("Alice", alice_queue)
message_router.add_route("Bob", bob_queue)

message_router.route_message("Hello, Alice!", "Alice")
message_router.route_message("Hello, Bob!", "Bob")

alice_message = alice_queue.dequeue_message()
bob_message = bob_queue.dequeue_message()

print(alice_message)  # Hello, Alice!
print(bob_message)  # Hello, Bob!

class Group:
    def __init__(self, name):
        self.name = name
        self.members = []

    def add_member(self, user):
        self.members.append(user)

    def send_message(self, message):
        for member in self.members:
            member.receive_message(self, message)

class User:
    def __init__(self, username):
        self.username = username
        self.groups = []

    def join_group(self, group):
        self.groups.append(group)
        group.add_member(self)

    def send_group_message(self, group, message):
        group.send_message(f"{self.username}: {message}")

    def receive_message(self, group, message):
        print(f"{group.name} - {message}")

# Example usage
user1 = User("John")
user2 = User("Alice")
user3 = User("Bob")

group1 = Group("Group 1")
user1.join_group(group1)
user2.join_group(group1)
user3.join_group(group1)

user1.send_group_message(group1, "Hello, everyone!")
user2.send_group_message(group1, "Hi, John!")
user3.send_group_message(group1, "Hey, Alice!")

# Output:
# Group 1 - John: Hello, everyone!
# Group 1 - Alice: Hi, John!
# Group 1 - Bob: Hey, Alice!

import base64

class User:
    def __init__(self, username):
        self.username = username

    def send_photo_message(self, recipient, photo):
        encoded_photo = base64.b64encode(photo)
        recipient.receive_photo_message(self, encoded_photo)

    def receive_photo_message(self, sender, encoded_photo):
        photo = base64.b64decode(encoded_photo)
        # Process the received photo

# Example usage
user1 = User("John")
user2 = User("Alice")

photo_data = b"..."  # Placeholder for actual photo data

user1.send_photo_message(user2, photo_data)

from queue import Queue

class MessageQueue:
    def __init__(self):
        self.queue = Queue()

    def enqueue_message(self, message):
        self.queue.put(message)

    def dequeue_message(self):
        return self.queue.get()

class User:
    def __init__(self, username):
        self.username = username
        self.message_queue = MessageQueue()

    def send_message(self, recipient, message):
        if recipient.is_online():
            recipient.receive_message(self, message)
        else:
            recipient.message_queue.enqueue_message((self, message))

    def receive_message(self, sender, message):
        print(f"Received message from {sender.username}: {message}")

    def is_online(self):
        # Logic to determine if the user is currently online
        return True

class Device:
    def __init__(self, user):
        self.user = user
        self.message_queue = user.message_queue

    def sync_messages(self):
        while not self.message_queue.queue.empty():
            sender, message = self.message_queue.dequeue_message()
            self.user.receive_message(sender, message)

# Example usage
user1 = User("John")
user2 = User("Alice")
device = Device(user1)

user1.send_message(user2, "Hello, Alice!")
device.sync_messages()

# Output:
# Received message from John: Hello, Alice!

class User:
    def __init__(self, username):
        self.username = username
        self.notification_preference = True

    def receive_message(self, sender, message):
        if self.notification_preference:
            self.send_push_notification(f"New message from {sender.username}")

    def send_push_notification(self, notification):
        # Code for sending push notification to user's device
        print(f"Push notification: {notification}")

# Example usage
user1 = User("John")
user2 = User("Alice")

user1.receive_message(user2, "Hello, John!")

# Output:
# Push notification: New message from Alice

class User:
    def __init__(self, username):
        self.username = username
        self.message_history = []

    def receive_message(self, sender, message):
        self.message_history.append((sender, message))

    def search_messages(self, keyword):
        results = []
        for sender, message in self.message_history:
            if keyword in message:
                results.append((sender, message))
        return results

# Example usage
user1 = User("John")
user2 = User("Alice")

user1.receive_message(user2, "Hello, John!")
user1.receive_message(user2, "How are you, John?")
user1.receive_message(user2, "John, are you there?")

results = user1.search_messages("John")

print(results)
# Output: [(Alice, "Hello, John!"), (Alice, "How are you, John?"), (Alice, "John, are you there?")]

from cryptography.fernet import Fernet

class User:
    def __init__(self, username, encryption_key):
        self.username = username
        self.encryption_key = encryption_key

    def send_encrypted_message(self, recipient, message):
        cipher = Fernet(self.encryption_key)
        encrypted_message = cipher.encrypt(message.encode())
        recipient.receive_encrypted_message(self, encrypted_message)

    def receive_encrypted_message(self, sender, encrypted_message):
        cipher = Fernet(self.encryption_key)
        decrypted_message = cipher.decrypt(encrypted_message).decode()
        print(f"Received message from {sender.username}: {decrypted_message}")

# Example usage
user1 = User("John", b"encryption_key_1")
user2 = User("Alice", b"encryption_key_2")

user1.send_encrypted_message(user2, "Hello, Alice!")

# Output:
# Received message from John: Hello, Alice!

from functools import lru_cache

class MessageStorage:
    @lru_cache(maxsize=1000)  # Caching up to 1000 most recently used messages
    def get_message(self, message_id):
        # Code to fetch message from storage
        return message

    def store_message(self, message):
        # Code to store message in storage
        pass

# Example usage
message_storage = MessageStorage()

message_id = 12345
message = message_storage.get_message(message_id)  # First access triggers retrieval
print(message)  # Prints the retrieved message

message = "New message"
message_storage.store_message(message)
message_storage.get_message(message_id)  # Retrieves from cache, not from storage

class Server:
    def __init__(self, server_id):
        self.server_id = server_id
        self.is_running = True

    def process_message(self, message):
        if self.is_running:
            # Code to process the message
            print(f"Message processed on server {self.server_id}")
        else:
            raise ServerFailureException("Server is not running")

class ServerFailureException(Exception):
    pass

# Example usage
server = Server(1)

try:
    server.process_message("Hello, server!")
except ServerFailureException as e:
    print(f"Server failure occurred: {e}")

class DistributedCache:
    def __init__(self):
        self.cache = {}

    def set(self, key, value):
        self.cache[key] = value

    def get(self, key):
        return self.cache.get(key, None)

    def delete(self, key):
        if key in self.cache:
            del self.cache[key]

cache = DistributedCache()

# Simulating video uploads
videos_uploaded_per_day = 9_000_000

for video_id in range(videos_uploaded_per_day):
    cache.set(f"video_{video_id}", f"video_content_{video_id}")

# Simulating video views
videos_watched_per_day = 900_000_000

for user_id in range(1, 300_000_001):  # Assuming user IDs from 1 to 300 million
    for _ in range(3):  # Each user watches 3 videos
        video_id = random.randint(0, videos_uploaded_per_day - 1)
        cache.get(f"video_{video_id}")

# Checking cache statistics
total_cache_size = len(cache.cache)
print(f"Total cache size: {total_cache_size}")

# Checking storage estimation
video_size_mb = 80
total_storage_tb = videos_uploaded_per_day * video_size_mb / 1_000_000
total_storage_pb = total_storage_tb * 5 * 365 / 1_000

print(f"Total storage per day: {total_storage_tb:.2f} TB")
print(f"Total storage for next 3 years: {total_storage_pb:.2f} PB")

import java.util.HashMap;
import java.util.Map;

class DistributedCache {
    private Map<String, Object> cache;
    
    public DistributedCache() {
        this.cache = new HashMap<>();
    }
    
    public void put(String key, Object value) {
        cache.put(key, value);
    }
    
    public Object get(String key) {
        return cache.get(key);
    }
    
    public void remove(String key) {
        cache.remove(key);
    }
    
    // Additional methods for cache eviction, cache statistics, etc.
    // ...
}

class CacheNode {
    private String nodeId;
    private String ipAddress;
    private int port;
    private DistributedCache distributedCache;
    
    public CacheNode(String nodeId, String ipAddress, int port) {
        this.nodeId = nodeId;
        this.ipAddress = ipAddress;
        this.port = port;
        this.distributedCache = new DistributedCache();
    }
    
    // Getters and setters for attributes
    
    public DistributedCache getDistributedCache() {
        return distributedCache;
    }
    
    // ...
}

class CacheCluster {
    private Map<String, CacheNode> nodes;
    
    public CacheCluster() {
        this.nodes = new HashMap<>();
    }
    
    public void addNode(CacheNode node) {
        nodes.put(node.getNodeId(), node);
    }
    
    public void removeNode(String nodeId) {
        nodes.remove(nodeId);
    }
    
    public CacheNode getNode(String nodeId) {
        return nodes.get(nodeId);
    }
    
    public void put(String key, Object value) {
        CacheNode node = getNodeForKey(key);
        node.getDistributedCache().put(key, value);
    }
    
    public Object get(String key) {
        CacheNode node = getNodeForKey(key);
        return node.getDistributedCache().get(key);
    }
    
    public void remove(String key) {
        CacheNode node = getNodeForKey(key);
        node.getDistributedCache().remove(key);
    }
    
    private CacheNode getNodeForKey(String key) {
        // Logic to determine the cache node responsible for the given key
        // ...
    }
    
    // Additional methods for cache management, node failure handling, etc.
    // ...
}

public class Main {
    public static void main(String[] args) {
        CacheNode node1 = new CacheNode("Node1", "192.168.0.1", 8080);
        CacheNode node2 = new CacheNode("Node2", "192.168.0.2", 8080);
        
        CacheCluster cluster = new CacheCluster();
        cluster.addNode(node1);
        cluster.addNode(node2);
        
        cluster.put("key1", "value1");
        cluster.put("key2", "value2");
        
        Object value1 = cluster.get("key1");
        Object value2 = cluster.get("key2");
        
        System.out.println("Value for key1: " + value1);
        System.out.println("Value for key2: " + value2);
    }
}

GET /cache-cluster
- Description: Get information about the cache cluster.
- Response:
  - 200 OK: Returns information about the cache cluster.
  - 401 Unauthorized: Unauthorized access.
  - 500 Internal Server Error: An error occurred on the server.

POST /cache-cluster/nodes
- Description: Add a new cache node to the cluster.
- Request:
  - Body: Node information (e.g., nodeId, ipAddress, port).
- Response:
  - 201 Created: Cache node added successfully.
  - 400 Bad Request: Invalid request or missing information.
  - 401 Unauthorized: Unauthorized access.
  - 500 Internal Server Error: An error occurred on the server.

DELETE /cache-cluster/nodes/{nodeId}
- Description: Remove a cache node from the cluster.
- Parameters:
  - {nodeId}: Identifier of the cache node to remove.
- Response:
  - 204 No Content: Cache node removed successfully.
  - 401 Unauthorized: Unauthorized access.
  - 404 Not Found: Cache node not found.
  - 500 Internal Server Error: An error occurred on the server.

GET /cache-cluster/nodes/{nodeId}/cache/{key}
- Description: Get the value associated with the specified key in the cache node.
- Parameters:
  - {nodeId}: Identifier of the cache node.
  - {key}: Key to retrieve the value.
- Response:
  - 200 OK: Returns the value associated with the key.
  - 401 Unauthorized: Unauthorized access.
  - 404 Not Found: Key not found.
  - 500 Internal Server Error: An error occurred on the server.

POST /cache-cluster/nodes/{nodeId}/cache/{key}
- Description: Insert or update the value associated with the specified key in the cache node.
- Parameters:
  - {nodeId}: Identifier of the cache node.
  - {key}: Key to insert or update.
- Request:
  - Body: Value to insert or update.
- Response:
  - 201 Created: Value inserted or updated successfully.
  - 400 Bad Request: Invalid request or missing information.
  - 401 Unauthorized: Unauthorized access.
  - 500 Internal Server Error: An error occurred on the server.

DELETE /cache-cluster/nodes/{nodeId}/cache/{key}
- Description: Remove the key-value pair from the cache node.
- Parameters:
  - {nodeId}: Identifier of the cache node.
  - {key}: Key to remove.
- Response:
  - 204 No Content: Key-value pair removed successfully.
  - 401 Unauthorized: Unauthorized access.
  - 404 Not Found: Key not found.
  - 500 Internal Server Error: An error occurred on the server.

from flask import Flask, request, jsonify

class DistributedCache:
    def __init__(self):
        self.cache = {}

    def set(self, key, value):
        self.cache[key] = value

    def get(self, key):
        return self.cache.get(key, None)

    def delete(self, key):
        if key in self.cache:
            del self.cache[key]

app = Flask(__name__)
cache = DistributedCache()

@app.route("/cache/set", methods=["POST"])
def set_key_value():
    data = request.get_json()
    if "key" not in data or "value" not in data:
        return jsonify({"error": "Invalid request"}), 400
    cache.set(data["key"], data["value"])
    return jsonify({"message": "Key-value pair set successfully"}), 200

@app.route("/cache/get", methods=["GET"])
def get_value():
    key = request.args.get("key")
    value = cache.get(key)
    if value is None:
        return jsonify({"error": "Key not found"}), 404
    return jsonify({"value": value}), 200

@app.route("/cache/delete", methods=["DELETE"])
def delete_key():
    key = request.args.get("key")
    cache.delete(key)
    return jsonify({"message": "Key deleted successfully"}), 200

if __name__ == "__main__":
    app.run()

import hashlib

class DistributedCache:
    def __init__(self, num_partitions):
        self.num_partitions = num_partitions
        self.partitions = [[] for _ in range(num_partitions)]

    def get_partition(self, key):
        hash_value = int(hashlib.md5(key.encode()).hexdigest(), 16)
        partition_index = hash_value % self.num_partitions
        return partition_index

    def put(self, key, value):
        partition_index = self.get_partition(key)
        self.partitions[partition_index].append((key, value))

    def get(self, key):
        partition_index = self.get_partition(key)
        partition = self.partitions[partition_index]
        for stored_key, value in partition:
            if stored_key == key:
                return value
        return None

    def delete(self, key):
        partition_index = self.get_partition(key)
        partition = self.partitions[partition_index]
        for i, (stored_key, _) in enumerate(partition):
            if stored_key == key:
                del partition[i]
                break

class DistributedCache:
    def __init__(self, num_replicas):
        self.num_replicas = num_replicas
        self.replicas = [[] for _ in range(num_replicas)]

    def replicate(self, key, value):
        for i in range(self.num_replicas):
            self.replicas[i].append((key, value))

    def put(self, key, value):
        self.replicate(key, value)

    def get(self, key):
        for replica in self.replicas:
            for stored_key, value in replica:
                if stored_key == key:
                    return value
        return None

    def delete(self, key):
        for replica in self.replicas:
            for i, (stored_key, _) in enumerate(replica):
                if stored_key == key:
                    del replica[i]
                    break

from collections import OrderedDict

class DistributedCache:
    def __init__(self, capacity):
        self.capacity = capacity
        self.cache = OrderedDict()

    def put(self, key, value):
        if key in self.cache:
            del self.cache[key]
        elif len(self.cache) == self.capacity:
            self.cache.popitem(last=False)
        self.cache[key] = value

    def get(self, key):
        if key in self.cache:
            value = self.cache[key]
            del self.cache[key]
            self.cache[key] = value
            return value
        return None

    def delete(self, key):
        if key in self.cache:
            del self.cache[key]

class DistributedCache:
    def __init__(self):
        self.cache = {}

    def put(self, key, value):
        self.cache[key] = value

    def get(self, key):
        return self.cache.get(key, None)

    def delete(self, key):
        if key in self.cache:
            del self.cache[key]

    def invalidate(self, key):
        self.delete(key)

from flask import Flask, request, jsonify

app = Flask(__name__)

# Sample data for activities
activities_data = {}

@app.route('/api/v1/log_activity', methods=['POST'])
def log_activity():
    data = request.get_json()
    user_id = data.get("user_id")
    activity = data.get("activity")

    if not user_id or not activity:
        return jsonify({"error": "Invalid input data. User ID and activity details are required."}), 400

    # Save activity data to the database (in-memory dictionary for demonstration purposes)
    if user_id not in activities_data:
        activities_data[user_id] = []

    activities_data[user_id].append(activity)

    return jsonify({"message": "Activity logged successfully"}), 201

@app.route('/api/v1/get_activities', methods=['GET'])
def get_activities():
    user_id = request.args.get('user_id')

    if not user_id:
        return jsonify({"error": "User ID is required in the query parameter."}), 400

    # Retrieve activities for the user from the database (in-memory dictionary for demonstration purposes)
    user_activities = activities_data.get(user_id, [])

    return jsonify({"user_id": user_id, "activities": user_activities}), 200

if __name__ == '__main__':
    app.run(debug=True)

from flask import Flask, request, jsonify
app = Flask(__name__)

# Sample data to be stored in the server
users = {}
health_data = {}
diet_plans = {}
workout_plans = {}

# User Management Service
@app.route('/api/v1/users', methods=['POST'])
def create_user():
    data = request.get_json()
    user_id = data.get('user_id')
    if user_id in users:
        return "User already exists", 409
    username = data.get('username')
    email = data.get('email')
    password = data.get('password')
    users[user_id] = {'username': username, 'email': email, 'password': password}
    return "User created successfully", 201

@app.route('/api/v1/users/<user_id>', methods=['GET'])
def get_user(user_id):
    if user_id in users:
        return jsonify(users[user_id]), 200
    return "User not found", 404

@app.route('/api/v1/users/<user_id>', methods=['PATCH'])
def update_user(user_id):
    if user_id in users:
        data = request.get_json()
        users[user_id].update(data)
        return "User profile updated successfully", 200
    return "User not found", 404

# Health Data Service
@app.route('/api/v1/healthdata', methods=['POST'])
def record_health_data():
    data = request.get_json()
    user_id = data.get('user_id')
    if user_id not in users:
        return "User not found", 404
    health_data[user_id] = data
    return "Health data recorded successfully", 201

@app.route('/api/v1/healthdata/<user_id>', methods=['GET'])
def get_health_data(user_id):
    if user_id in health_data:
        return jsonify(health_data[user_id]), 200
    return "Health data not found", 404

# Diet Plan Service
@app.route('/api/v1/dietplan', methods=['POST'])
def create_diet_plan():
    data = request.get_json()
    user_id = data.get('user_id')
    if user_id not in users:
        return "User not found", 404
    diet_plans[user_id] = data
    return "Diet plan created successfully", 201

@app.route('/api/v1/dietplan/<user_id>', methods=['GET'])
def get_diet_plan(user_id):
    if user_id in diet_plans:
        return jsonify(diet_plans[user_id]), 200
    return "Diet plan not found", 404

# Workout Plan Service
@app.route('/api/v1/workoutplan', methods=['POST'])
def create_workout_plan():
    data = request.get_json()
    user_id = data.get('user_id')
    if user_id not in users:
        return "User not found", 404
    workout_plans[user_id] = data
    return "Workout plan created successfully", 201

@app.route('/api/v1/workoutplan/<user_id>', methods=['GET'])
def get_workout_plan(user_id):
    if user_id in workout_plans:
        return jsonify(workout_plans[user_id]), 200
    return "Workout plan not found", 404

if __name__ == '__main__':
    app.run()

{
  "name": "John Doe",
  "email": "[email protected]",
  "password": "secure_password"
}

{
  "message": "User registered successfully",
  "user_id": "user123"
}

from flask import Flask, request, jsonify

app = Flask(__name__)

@app.route('/api/v1/register', methods=['POST'])
def register_user():
    data = request.get_json()
    # Validate input data (e.g., check if email is not already registered)
    # Perform user registration and save user data to the database
    # Generate a unique user_id
    user_id = "user123"
    return jsonify({"message": "User registered successfully", "user_id": user_id}), 201

if __name__ == '__main__':
    app.run(debug=True)

Authorization: Bearer <user_access_token>

{
  "user_id": "user123",
  "diet_plan": {
    "breakfast": "Oatmeal with fruits",
    "lunch": "Grilled chicken with salad",
    "dinner": "Salmon with steamed vegetables",
    "calories": 1800
  }
}

@app.route('/api/v1/diet_plan', methods=['GET'])
def get_diet_plan():
    user_access_token = request.headers.get('Authorization').split()[1]
    # Validate and verify the user_access_token
    user_id = "user123"
    diet_plan = {
        "breakfast": "Oatmeal with fruits",
        "lunch": "Grilled chicken with salad",
        "dinner": "Salmon with steamed vegetables",
        "calories": 1800
    }
    return jsonify({"user_id": user_id, "diet_plan": diet_plan}), 200

Authorization: Bearer <user_access_token>

{
  "steps": 8000,
  "distance": 5.2,
  "active_minutes": 60
}

{
  "message": "Activity logged successfully"
}

@app.route('/api/v1/activity_log', methods=['POST'])
def log_activity():
    user_access_token = request.headers.get('Authorization').split()[1]
    # Validate and verify the user_access_token
    # Retrieve user_id from the token
    data = request.get_json()
    steps = data["steps"]
    distance = data["distance"]
    active_minutes = data["active_minutes"]
    # Save activity data to the database
    return jsonify({"message": "Activity logged successfully"}), 201

from flask import Flask, request, jsonify

app = Flask(__name__)

# Sample data for user registration and diet plan retrieval
users_data = {}
users_diet_plans = {}

@app.route('/api/v1/register', methods=['POST'])
def register_user():
    data = request.get_json()
    name = data.get("name")
    email = data.get("email")
    password = data.get("password")

    if not name or not email or not password:
        return jsonify({"error": "Invalid input data. Name, email, and password are required."}), 400

    # Check if the email is already registered
    if email in users_data:
        return jsonify({"error": "User with this email already exists."}), 409

    # Generate a unique user_id (you can use a library like uuid for this purpose)
    user_id = "user123"

    # Save user data to the database (in-memory dictionary for demonstration purposes)
    users_data[email] = {
        "name": name,
        "password": password,
        "user_id": user_id
    }

    return jsonify({"message": "User registered successfully", "user_id": user_id}), 201

@app.route('/api/v1/diet_plan', methods=['GET'])
def get_diet_plan():
    user_access_token = request.headers.get('Authorization').split()[1]

    # Validate and verify the user_access_token (you can use a JWT library for this purpose)
    # For demonstration, we'll assume the user_access_token is valid and contains the user's email.
    email = "[email protected]"

    # Retrieve the user_id associated with the given email
    user_id = users_data.get(email, {}).get("user_id")

    if not user_id:
        return jsonify({"error": "User not found."}), 404

    # Check if a diet plan exists for the user
    if user_id not in users_diet_plans:
        return jsonify({"error": "Diet plan not found for the user."}), 404

    # Retrieve the diet plan for the user
    diet_plan = users_diet_plans[user_id]

    return jsonify({"user_id": user_id, "diet_plan": diet_plan}), 200

@app.route('/api/v1/activity_log', methods=['POST'])
def log_activity():
    user_access_token = request.headers.get('Authorization').split()[1]

    # Validate and verify the user_access_token (you can use a JWT library for this purpose)
    # For demonstration, we'll assume the user_access_token is valid and contains the user's email.
    email = "[email protected]"

    # Retrieve the user_id associated with the given email
    user_id = users_data.get(email, {}).get("user_id")

    if not user_id:
        return jsonify({"error": "User not found."}), 404

    data = request.get_json()
    steps = data.get("steps")
    distance = data.get("distance")
    active_minutes = data.get("active_minutes")

    if not steps or not distance or not active_minutes:
        return jsonify({"error": "Invalid input data. Steps, distance, and active_minutes are required."}), 400

    # Save activity data to the database (in-memory dictionary for demonstration purposes)
    # You can use a database or storage service for production implementation.
    activity_log = {
        "steps": steps,
        "distance": distance,
        "active_minutes": active_minutes
    }

    if user_id not in users_diet_plans:
        users_diet_plans[user_id] = []

    users_diet_plans[user_id].append(activity_log)

    return jsonify({"message": "Activity logged successfully"}), 201

if __name__ == '__main__':
    app.run(debug=True)

from flask import Flask, request, jsonify

app = Flask(__name__)

# Sample data for user registration, personalized diet plans, and activity logs
users_data = {}
users_diet_plans = {}
users_activity_logs = {}

@app.route('/api/v1/register', methods=['POST'])
def register_user():
    data = request.get_json()
    name = data.get("name")
    email = data.get("email")
    password = data.get("password")

    if not name or not email or not password:
        return jsonify({"error": "Invalid input data. Name, email, and password are required."}), 400

    # Check if the email is already registered
    if email in users_data:
        return jsonify({"error": "User with this email already exists."}), 409

    # Generate a unique user_id (you can use a library like uuid for this purpose)
    user_id = "user123"

    # Save user data to the database (in-memory dictionary for demonstration purposes)
    users_data[email] = {
        "name": name,
        "password": password,
        "user_id": user_id
    }

    # Initialize user's diet plan and activity log
    users_diet_plans[user_id] = []
    users_activity_logs[user_id] = []

    return jsonify({"message": "User registered successfully", "user_id": user_id}), 201


@app.route('/api/v1/diet_plan', methods=['POST'])
def get_personalized_diet_plan():
    user_access_token = request.headers.get('Authorization').split()[1]

    # Validate and verify the user_access_token (you can use a JWT library for this purpose)
    # For demonstration, we'll assume the user_access_token is valid and contains the user's email.
    email = "[email protected]"

    # Retrieve the user_id associated with the given email
    user_id = users_data.get(email, {}).get("user_id")

    if not user_id:
        return jsonify({"error": "User not found."}), 404

    # Create a personalized diet plan for the user (you can use external APIs or algorithms for this)
    diet_plan = {
        "breakfast": "Oatmeal with fruits",
        "lunch": "Grilled chicken with salad",
        "dinner": "Salmon with steamed vegetables",
        "calories": 1800
    }

    users_diet_plans[user_id].append(diet_plan)

    return jsonify({"user_id": user_id, "diet_plan": diet_plan}), 200


@app.route('/api/v1/activity_log', methods=['POST'])
def log_activity():
    user_access_token = request.headers.get('Authorization').split()[1]

    # Validate and verify the user_access_token (you can use a JWT library for this purpose)
    # For demonstration, we'll assume the user_access_token is valid and contains the user's email.
    email = "[email protected]"

    # Retrieve the user_id associated with the given email
    user_id = users_data.get(email, {}).get("user_id")

    if not user_id:
        return jsonify({"error": "User not found."}), 404

    data = request.get_json()
    steps = data.get("steps")
    distance = data.get("distance")
    active_minutes = data.get("active_minutes")

    if not steps or not distance or not active_minutes:
        return jsonify({"error": "Invalid input data. Steps, distance, and active_minutes are required."}), 400

    # Save activity data to the database (in-memory dictionary for demonstration purposes)
    activity_log = {
        "steps": steps,
        "distance": distance,
        "active_minutes": active_minutes
    }

    users_activity_logs[user_id].append(activity_log)

    return jsonify({"message": "Activity logged successfully"}), 201

if __name__ == '__main__':
    app.run(debug=True)

import time
import random

class ParkingLotSystem:
    def __init__(self, capacity):
        self.capacity = capacity
        self.available_spaces = capacity
        self.parked_vehicles = set()
        self.reservations = {}

    def vehicle_entry(self, vehicle_id):
        if self.available_spaces > 0:
            self.available_spaces -= 1
            self.parked_vehicles.add(vehicle_id)
            return True
        else:
            return False

    def vehicle_exit(self, vehicle_id):
        if vehicle_id in self.parked_vehicles:
            self.available_spaces += 1
            self.parked_vehicles.remove(vehicle_id)
            return True
        else:
            return False

    def make_reservation(self, vehicle_id, duration):
        if vehicle_id not in self.reservations and self.available_spaces > 0:
            self.reservations[vehicle_id] = time.time() + duration
            return True
        else:
            return False

    def check_reservation(self, vehicle_id):
        if vehicle_id in self.reservations:
            return self.reservations[vehicle_id] - time.time()
        else:
            return None

    def cancel_reservation(self, vehicle_id):
        if vehicle_id in self.reservations:
            del self.reservations[vehicle_id]
            return True
        else:
            return False


# Example usage:
if __name__ == "__main__":
    parking_lot_system = ParkingLotSystem(capacity=1000)

    # Simulate vehicle entry and exit
    for i in range(3600):
        vehicle_id = f"Vehicle-{i+1}"
        if parking_lot_system.vehicle_entry(vehicle_id):
            print(f"{vehicle_id} parked successfully.")
        else:
            print(f"{vehicle_id} couldn't park. Parking lot full.")
        parked_duration = random.randint(1, 4) * 3600  # Random parking duration between 1 to 4 hours
        time.sleep(parked_duration)  # Simulate parked duration
        if parking_lot_system.vehicle_exit(vehicle_id):
            print(f"{vehicle_id} exited successfully.")
        else:
            print(f"{vehicle_id} not found in the parking lot.")

    # Simulate parking reservations
    for i in range(180000):
        vehicle_id = f"Reservation-{i+1}"
        reservation_time = random.randint(1, 3) * 3600  # Random reservation time between 1 to 3 hours
        if parking_lot_system.make_reservation(vehicle_id, reservation_time):
            print(f"{vehicle_id} reservation made successfully.")
        else:
            print(f"{vehicle_id} couldn't make reservation. No available spaces.")
        time.sleep(random.randint(1, 5))  # Simulate time between reservation attempts

    # Check reservations and cancel them
    for i in range(180000):
        vehicle_id = f"Reservation-{i+1}"
        remaining_time = parking_lot_system.check_reservation(vehicle_id)
        if remaining_time is not None:
            print(f"{vehicle_id} has {remaining_time/3600:.2f} hours remaining in reservation.")
        else:
            print(f"{vehicle_id} doesn't have an active reservation.")
        if random.random() < 0.1:  # 10% chance to cancel the reservation
            if parking_lot_system.cancel_reservation(vehicle_id):
                print(f"{vehicle_id} reservation canceled.")
            else:
                print(f"{vehicle_id} doesn't have an active reservation to cancel.")
        time.sleep(random.randint(1, 5))  # Simulate time between reservation checks and cancellations

+---------------+       +--------------+       +-------------------+
|   Parking     |       |   Vehicle    |       |    Payment        |
+---------------+       +--------------+       +-------------------+
| parking_id (PK)|       | vehicle_id   |       | payment_id (PK)   |
| location      |       | type         |       | parking_id (FK)   |
| capacity      |       | plate_number |       | amount            |
| available     |       +--------------+        | payment_method    |
+---------------+                               | transaction_time  |
                                                 +-------------------+

Parking Management:

getParkingInfo(parking_id): Retrieves parking information, including location, capacity, and availability status.

checkAvailability(parking_id, timestamp): Checks if parking space is available at the given timestamp.

reserveParking(parking_id, user_id, timestamp): Reserves a parking space for the user at the specified time.

cancelReservation(reservation_id): Cancels the user's parking reservation.

Payment Management:

calculateParkingFee(parking_id, entry_time, exit_time): Calculates the parking fee based on entry and exit times.

processPayment(user_id, parking_id, amount, payment_method): Initiates the payment process for the parking fee.

generateInvoice(user_id, parking_id, entry_time, exit_time, amount): Generates an invoice for the parking transaction.

User Management:

registerUser(name, email, password): Registers a new user in the system.

loginUser(email, password): Authenticates the user and generates a session token.

getUserInfo(user_id): Retrieves user information such as name, email, and reservation history.

class ParkingLot:
    def __init__(self, capacity):
        self.capacity = capacity
        self.available_spaces = capacity
        self.parked_vehicles = set()

    def vehicle_entry(self, vehicle_id):
        if self.available_spaces > 0:
            self.available_spaces -= 1
            self.parked_vehicles.add(vehicle_id)
            return True
        else:
            return False

    def vehicle_exit(self, vehicle_id):
        if vehicle_id in self.parked_vehicles:
            self.available_spaces += 1
            self.parked_vehicles.remove(vehicle_id)
            return True
        else:
            return False


class User:
    def __init__(self, user_id, username, password):
        self.user_id = user_id
        self.username = username
        self.password = password


class Reservation:
    def __init__(self, reservation_id, user, parking_lot, timestamp, duration):
        self.reservation_id = reservation_id
        self.user = user
        self.parking_lot = parking_lot
        self.timestamp = timestamp
        self.duration = duration

Parking API:

GET /parking/{parking_id}: Get parking information.
GET /parking/{parking_id}/availability: Get parking availability status.
POST /parking/{parking_id}/reserve: Reserve a parking space.
DELETE /reservation/{reservation_id}: Cancel a parking reservation.

Payment API:

POST /payment/{parking_id}: Process parking payment.
GET /invoice/{invoice_id}: Get payment invoice.

User API:

POST /user/register: Register a new user.
POST /user/login: User login.
GET /user/{user_id}: Get user information.

from flask import Flask, jsonify, request

app = Flask(__name__)

# Sample authentication middleware (you can integrate actual authentication here)
def authenticate_request():
    # Implement actual authentication logic here
    return True

# Sample versioning middleware (you can implement versioning if needed)
def check_api_version():
    # Implement versioning logic here
    return True

@app.route("/parking/<int:parking_id>", methods=["GET"])
def get_parking_info_route(parking_id):
    if authenticate_request() and check_api_version():
        parking_info = get_parking_info(parking_id)
        return jsonify(parking_info)
    return jsonify({"error": "Unauthorized or unsupported API version"}), 401

@app.route("/parking/<int:parking_id>/availability", methods=["GET"])
def check_availability_route(parking_id):
    if authenticate_request() and check_api_version():
        timestamp = int(request.args.get("timestamp", 0))
        available = check_availability(parking_id, timestamp)
        return jsonify({"available": available})
    return jsonify({"error": "Unauthorized or unsupported API version"}), 401

@app.route("/parking/<int:parking_id>/reserve", methods=["POST"])
def reserve_parking_route(parking_id):
    if authenticate_request() and check_api_version():
        user_id = int(request.json.get("user_id", 0))
        timestamp = int(request.json.get("timestamp", 0))
        reservation_id = reserve_parking(parking_id, user_id, timestamp)
        return jsonify({"reservation_id": reservation_id})
    return jsonify({"error": "Unauthorized or unsupported API version"}), 401

@app.route("/reservation/<int:reservation_id>", methods=["DELETE"])
def cancel_reservation_route(reservation_id):
    if authenticate_request() and check_api_version():
        success = cancel_reservation(reservation_id)
        return jsonify({"success": success})
    return jsonify({"error": "Unauthorized or unsupported API version"}), 401

@app.route("/payment/<int:parking_id>", methods=["POST"])
def process_payment_route(parking_id):
    if authenticate_request() and check_api_version():
        user_id = int(request.json.get("user_id", 0))
        amount = float(request.json.get("amount", 0))
        payment_method = request.json.get("payment_method", "")
        success = process_payment(user_id, parking_id, amount, payment_method)
        return jsonify({"success": success})
    return jsonify({"error": "Unauthorized or unsupported API version"}), 401

@app.route("/invoice/<int:invoice_id>", methods=["GET"])
def get_invoice_route(invoice_id):
    if authenticate_request() and check_api_version():
        # Assume you have a database to store invoices and retrieve them here.
        # For the sake of simplicity, let's generate a dummy invoice instead.
        user_id = 123
        parking_id = 456
        entry_time = 1632328200
        exit_time = 1632349200
        amount = 10.50
        invoice = generate_invoice(user_id, parking_id, entry_time, exit_time, amount)
        return jsonify({"invoice": invoice})
    return jsonify({"error": "Unauthorized or unsupported API version"}), 401

if __name__ == "__main__":
    app.run(port=8080)

class ParkingLot:
    def __init__(self):
        self.parking_lots = {}
        self.reservations = {}
        self.next_reservation_id = 1

    def add_parking_lot(self, parking_id, location, capacity):
        self.parking_lots[parking_id] = {
            "location": location,
            "capacity": capacity,
            "available": capacity
        }

    def get_parking_info(self, parking_id):
        return self.parking_lots.get(parking_id, None)

    def check_availability(self, parking_id, timestamp):
        parking_info = self.parking_lots.get(parking_id, None)
        if not parking_info:
            return False
        return parking_info["available"] > 0

    def reserve_parking(self, parking_id, user_id, timestamp):
        parking_info = self.parking_lots.get(parking_id, None)
        if not parking_info or parking_info["available"] == 0:
            return -1
        reservation_id = self.next_reservation_id
        self.reservations[reservation_id] = {
            "parking_id": parking_id,
            "user_id": user_id,
            "timestamp": timestamp
        }
        self.parking_lots[parking_id]["available"] -= 1
        self.next_reservation_id += 1
        return reservation_id

    def cancel_reservation(self, reservation_id):
        reservation_info = self.reservations.get(reservation_id, None)
        if not reservation_info:
            return False
        parking_id = reservation_info["parking_id"]
        self.parking_lots[parking_id]["available"] += 1
        del self.reservations[reservation_id]
        return True


class PaymentManager:
    def calculate_parking_fee(self, parking_id, entry_time, exit_time):
        hourly_rate = 2  # Assume a fixed hourly rate of $2
        parking_duration = (exit_time - entry_time) // 3600  # Convert to hours
        total_fee = hourly_rate * parking_duration
        return total_fee

    def process_payment(self, user_id, parking_id, amount, payment_method):
        # Implement payment processing logic here (not implemented in this example)
        return True

    def generate_invoice(self, user_id, parking_id, entry_time, exit_time, amount):
        invoice = f"Invoice for User {user_id}:\n" \
                  f"Parking ID: {parking_id}\n" \
                  f"Entry Time: {entry_time}\n" \
                  f"Exit Time: {exit_time}\n" \
                  f"Total Amount: ${amount:.2f}"
        return invoice


# Example usage:
if __name__ == "__main__":
    parking_lot = ParkingLot()
    parking_lot.add_parking_lot(1, "Example Parking Lot", 100)

    user_id = 123
    timestamp = 1632328200
    parking_id = 1

    # Check parking availability
    available = parking_lot.check_availability(parking_id, timestamp)
    print("Parking Available:", available)

    # Reserve parking
    reservation_id = parking_lot.reserve_parking(parking_id, user_id, timestamp)
    print("Reservation ID:", reservation_id)

    # Cancel reservation
    success = parking_lot.cancel_reservation(reservation_id)
    print("Reservation Cancelled:", success)

    # Calculate parking fee
    exit_timestamp = 1632349200
    payment_manager = PaymentManager()
    total_fee = payment_manager.calculate_parking_fee(parking_id, timestamp, exit_timestamp)
    print("Total Parking Fee:", total_fee)

    # Generate invoice
    invoice = payment_manager.generate_invoice(user_id, parking_id, timestamp, exit_timestamp, total_fee)
    print("Invoice:")
    print(invoice)

import time

class ParkingLotSystem:
    def __init__(self, capacity):
        self.capacity = capacity
        self.available_spaces = capacity
        self.reservations = {}
        self.parking_log = {}

    def vehicle_entry(self, vehicle_id):
        if self.available_spaces > 0:
            timestamp = int(time.time())
            self.available_spaces -= 1
            self.parking_log[vehicle_id] = {"entry_time": timestamp}
            return True
        else:
            return False

    def vehicle_exit(self, vehicle_id):
        if vehicle_id in self.parking_log:
            timestamp = int(time.time())
            entry_time = self.parking_log[vehicle_id]["entry_time"]
            duration = timestamp - entry_time
            del self.parking_log[vehicle_id]
            self.available_spaces += 1
            return duration
        else:
            return None

    def get_available_spaces(self):
        return self.available_spaces

    def make_payment(self, vehicle_id, duration):
        hourly_rate = 2  # Assuming a fixed hourly rate of $2
        amount = hourly_rate * (duration // 3600)
        return amount

    def reserve_parking(self, vehicle_id, timestamp):
        if vehicle_id not in self.parking_log and self.available_spaces > 0:
            self.reservations[vehicle_id] = timestamp
            return True
        else:
            return False

    def is_parking_reserved(self, vehicle_id):
        return vehicle_id in self.reservations

    def get_reservation_timestamp(self, vehicle_id):
        return self.reservations.get(vehicle_id)

    def cancel_reservation(self, vehicle_id):
        if vehicle_id in self.reservations:
            del self.reservations[vehicle_id]
            return True
        else:
            return False


# Example usage:
if __name__ == "__main__":
    parking_lot_system = ParkingLotSystem(capacity=50)

    # Vehicle Entry
    vehicle_id_1 = "ABC123"
    success = parking_lot_system.vehicle_entry(vehicle_id_1)
    print(f"Vehicle Entry: {success}")

    # Parking Space Availability
    available_spaces = parking_lot_system.get_available_spaces()
    print(f"Available Spaces: {available_spaces}")

    # Reservation System
    vehicle_id_2 = "XYZ789"
    timestamp = int(time.time()) + 3600  # Reserve parking after 1 hour
    reservation_success = parking_lot_system.reserve_parking(vehicle_id_2, timestamp)
    print(f"Reservation Success: {reservation_success}")

    # Check Reservation Status
    is_reserved = parking_lot_system.is_parking_reserved(vehicle_id_2)
    print(f"Is Parking Reserved: {is_reserved}")

    # Get Reservation Timestamp
    reservation_timestamp = parking_lot_system.get_reservation_timestamp(vehicle_id_2)
    print(f"Reservation Timestamp: {reservation_timestamp}")

    # Cancel Reservation
    cancel_success = parking_lot_system.cancel_reservation(vehicle_id_2)
    print(f"Cancel Reservation Success: {cancel_success}")

    # Vehicle Exit and Payment
    duration = parking_lot_system.vehicle_exit(vehicle_id_1)
    if duration is not None:
        amount = parking_lot_system.make_payment(vehicle_id_1, duration)
        print(f"Vehicle Exit - Duration: {duration} seconds, Payment Amount: ${amount:.2f}")
    else:
        print("Vehicle not found in the parking log.")

import random
import time

# Mock data storage for scheduled events
scheduled_events = []

# Function to simulate scheduling an event
def schedule_event(user_id):
    event_id = random.randint(1000000, 9999999)  # Generate a random event ID
    event = {
        "event_id": event_id,
        "user_id": user_id,
        "start_time": "2023-07-20T14:00:00",  # Assuming the event starts at a fixed time
        "end_time": "2023-07-20T15:00:00",    # Assuming the event ends after one hour
        "location": "Meeting Room A",
        "participants": ["[email protected]", "[email protected]"]
    }
    scheduled_events.append(event)

# Function to read a scheduled event
def read_event(event_id):
    event = next((event for event in scheduled_events if event["event_id"] == event_id), None)
    return event

# Function to simulate the Calendly system
def simulate_calendly():
    total_users = 10000000
    active_users = 2000000
    events_per_user_per_day = 2
    read_to_write_ratio = 100

    # Simulate event scheduling
    for _ in range(active_users):
        user_id = random.randint(1, total_users)  # Assuming user IDs range from 1 to 10,000,000
        for _ in range(events_per_user_per_day):
            schedule_event(user_id)

    # Simulate event reading
    total_events = len(scheduled_events)
    read_requests = total_events * read_to_write_ratio

    # Print simulation results
    print(f"Total Users: {total_users}")
    print(f"Daily Active Users (DAU): {active_users}")
    print(f"Total Events Scheduled per Day: {len(scheduled_events)}")
    print(f"Storage Estimation per Day: {len(scheduled_events) * 1} KB")
    print(f"Storage Estimation for 3 Years: {len(scheduled_events) * 1 * 5 * 365} KB")
    print(f"Read Requests per Second: {read_requests / (3600 * 24)} requests/second")

if __name__ == '__main__':
    simulate_calendly()

class User:
    def __init__(self, user_id, username, password):
        self.user_id = user_id
        self.username = username
        self.password = password
        # Other user attributes and initialization

class Event:
    def __init__(self, event_id, user, start_time, end_time, location):
        self.event_id = event_id
        self.user = user
        self.start_time = start_time
        self.end_time = end_time
        self.location = location
        # Other event attributes and initialization

class Calendly:
    def __init__(self):
        self.users = {}  # Map of user_id to User object
        self.events = []  # List of Event objects

    def add_user(self, user):
        self.users[user.user_id] = user

    def get_user_by_id(self, user_id):
        return self.users.get(user_id)

    def create_event(self, user_id, start_time, end_time, location):
        user = self.get_user_by_id(user_id)
        if user is None:
            print("User not found")
            return

        event_id = generate_event_id()  # Generate a unique event ID
        event = Event(event_id, user, start_time, end_time, location)
        self.events.append(event)

        # Additional logic to update user's feed, notify participants, etc.
        # ...

    def get_user_events(self, user_id):
        user_events = []
        for event in self.events:
            if event.user.user_id == user_id:
                user_events.append(event)
        return user_events

# Import necessary libraries
from flask import Flask, jsonify, request
import uuid

app = Flask(__name__)

# Mock data storage for events
events_data = []

# Endpoint: Create Event
@app.route('/api/events', methods=['POST'])
def create_event():
    data = request.get_json()
    event_id = str(uuid.uuid4())
    event = {
        "event_id": event_id,
        "user_id": data["user_id"],
        "event_type_id": data["event_type_id"],
        "start_time": data["start_time"],
        "end_time": data["end_time"],
        "participants": data["participants"],
        "location": data["location"],
        "status": "confirmed"
    }
    events_data.append(event)
    return jsonify(event), 201

# Endpoint: Get User's Events
@app.route('/api/events', methods=['GET'])
def get_user_events():
    user_id = request.args.get('user_id')
    user_events = [event for event in events_data if event["user_id"] == user_id]
    return jsonify(user_events), 200

# Endpoint: Send Reminder
@app.route('/api/events/<string:event_id>/reminder', methods=['POST'])
def send_reminder(event_id):
    event = next((event for event in events_data if event["event_id"] == event_id), None)
    if event:
        # Your logic to send a reminder notification would be implemented here
        # For simplicity, we return a success message
        return jsonify({"message": "Reminder sent successfully."}), 200
    else:
        return jsonify({"message": "Event not found."}), 404

if __name__ == '__main__':
    app.run(debug=True)

Create User API

Method: POST
Endpoint: /users
Request Body: { "username": "john_doe", "password": "pass123" }
Response: 201 Created (with the newly created user's ID)

Get User API

Method: GET
Endpoint: /users/{user_id}
Response: 200 OK (with the user's information)

Create Event API

Method: POST
Endpoint: /users/{user_id}/events
Request Body: { "start_time": "2023-07-20T14:00:00", "end_time": "2023-07-20T15:00:00", "location": "Meeting Room A" }
Response: 201 Created (with the newly created event's ID)

Get User Events API

Method: GET
Endpoint: /users/{user_id}/events
Response: 200 OK (with the list of events created by the user)

from datetime import datetime

# Mock data storage for custom event types
custom_event_types = []

# Function to create custom event types
def create_custom_event_type(name, duration, location, meeting_preferences):
    event_type = {
        "name": name,
        "duration": duration,
        "location": location,
        "meeting_preferences": meeting_preferences
    }
    custom_event_types.append(event_type)

# Function to sync user's availability with existing commitments
def sync_user_availability(user_id, start_time, end_time):
    # Your logic to sync user's availability with their existing commitments would be implemented here
    print(f"User {user_id}'s availability is synced for {start_time} to {end_time}")

# Function to handle time zone conversions for scheduling
def convert_time_to_timezone(original_time, target_timezone):
    # Your logic for time zone conversions would be implemented here
    print(f"Converted time from {original_time} to {target_timezone}")
    return original_time  # For demonstration, returning the same time as no real conversion is done

# Mock data storage for integrated calendar and productivity tools
integrated_tools = ["Google Calendar", "Outlook", "Zoom"]

# Function to check if a given tool is integrated with Calendly
def is_tool_integrated(tool_name):
    return tool_name in integrated_tools

# Function to send automated reminders to all participants
def send_reminders(participants, event_time):
    for participant in participants:
        # Your logic to send automated reminders to participants would be implemented here
        print(f"Reminder sent to {participant} for the event at {event_time}")

# Mock data storage for team members and their availability
team_members = [
    {"name": "John", "availability": ["2023-07-20T14:00:00", "2023-07-20T15:00:00"]},
    {"name": "Jane", "availability": ["2023-07-20T13:00:00", "2023-07-20T16:00:00"]}
]

# Function to find the most suitable team member for scheduling
def find_most_suitable_team_member():
    # Your logic to find the most suitable team member based on their availability would be implemented here
    return team_members[0]

# Usage examples:

# Create custom event types
create_custom_event_type("Team Meeting", "1 hour", "Conference Room A", "In-person")

# Sync user's availability
sync_user_availability("user123", "2023-07-20T14:00:00", "2023-07-20T15:00:00")

# Convert time to a specific timezone
converted_time = convert_time_to_timezone("2023-07-20T14:00:00", "America/New_York")
print("Converted Time:", converted_time)

# Check if a tool is integrated
print(is_tool_integrated("Zoom"))  # Output: True
print(is_tool_integrated("Slack")) # Output: False

# Send automated reminders
participants = ["[email protected]", "[email protected]"]
event_time = "2023-07-20T14:00:00"
send_reminders(participants, event_time)

# Find the most suitable team member for scheduling
suitable_member = find_most_suitable_team_member()
print("Most Suitable Team Member:", suitable_member["name"])

from flask import Flask, request, jsonify

app = Flask(__name__)

# Sample data for demonstration purposes
users = {}
events = []
event_id_counter = 1

# Endpoint for creating a new user
@app.route('/users', methods=['POST'])
def create_user():
    data = request.json
    user_id = len(users) + 1
    user = User(user_id, data['username'], data['password'])
    users[user_id] = user
    return jsonify({"user_id": user_id}), 201

# Endpoint for getting a user's information
@app.route('/users/<int:user_id>', methods=['GET'])
def get_user(user_id):
    user = users.get(user_id)
    if user:
        return jsonify({"username": user.username}), 200
    else:
        return jsonify({"error": "User not found"}), 404

# Endpoint for creating a new event
@app.route('/users/<int:user_id>/events', methods=['POST'])
def create_event(user_id):
    data = request.json
    user = users.get(user_id)
    if user:
        global event_id_counter
        event_id = event_id_counter
        event_id_counter += 1
        event = Event(event_id, user, data['start_time'], data['end_time'], data['location'])
        events.append(event)
        return jsonify({"event_id": event_id}), 201
    else:
        return jsonify({"error": "User not found"}), 404

# Endpoint for getting a user's events
@app.route('/users/<int:user_id>/events', methods=['GET'])
def get_user_events(user_id):
    user = users.get(user_id)
    if user:
        user_events = []
        for event in events:
            if event.user.user_id == user_id:
                user_events.append({"event_id": event.event_id, "location": event.location})
        return jsonify({"events": user_events}), 200
    else:
        return jsonify({"error": "User not found"}), 404

if __name__ == '__main__':
    app.run(debug=True)

from flask import Flask, request, jsonify

app = Flask(__name__)

# Sample data for products
products = [
    {"id": 1, "name": "T-shirt", "brand": "Nike", "price": 25.99, "size": "M", "color": "Blue"},
    {"id": 2, "name": "Jeans", "brand": "Levi's", "price": 49.99, "size": "32", "color": "Black"},
    {"id": 3, "name": "Sneakers", "brand": "Adidas", "price": 74.99, "size": "9", "color": "White"},
]

# Storage variables
total_storage = 0
daily_storage_limit = 2 * 1024  # 2 TB/day

# User profiles
users = {}

# Product views
product_views = {}

# Product catalog
catalog = {}

# API for product view
@app.route('/api/products/<int:product_id>/view', methods=['POST'])
def view_product(product_id):
    user_id = request.json['user_id']

    if user_id not in users:
        users[user_id] = {
            "name": f"User {user_id}",
            "views": []
        }

    if product_id not in catalog:
        return jsonify({"message": "Product not found"}), 404

    users[user_id]['views'].append(product_id)

    if product_id not in product_views:
        product_views[product_id] = 0

    product_views[product_id] += 1

    return jsonify({"message": "Product viewed successfully!"}), 200

# API for adding a product to the catalog
@app.route('/api/products', methods=['POST'])
def add_product():
    data = request.json
    product_id = len(catalog) + 1

    catalog[product_id] = {
        "id": product_id,
        "name": data['name'],
        "brand": data['brand'],
        "price": data['price'],
        "size": data['size'],
        "color": data['color']
    }

    global total_storage
    total_storage += data['size_in_MB']

    if total_storage > daily_storage_limit:
        return jsonify({"message": "Daily storage limit exceeded. Please try again tomorrow."}), 400

    return jsonify({"message": "Product added to the catalog successfully!", "product_id": product_id}), 201

# API for getting product details
@app.route('/api/products/<int:product_id>', methods=['GET'])
def get_product(product_id):
    product = catalog.get(product_id)
    if product:
        return jsonify(product)
    return jsonify({"message": "Product not found"}), 404

# API for getting user details and views
@app.route('/api/users/<int:user_id>', methods=['GET'])
def get_user(user_id):
    user = users.get(user_id)
    if user:
        return jsonify(user)
    return jsonify({"message": "User not found"}), 404

if __name__ == '__main__':
    app.run()

import uuid
from datetime import datetime

class User:
    def __init__(self, user_id, username, password):
        self.user_id = user_id
        self.username = username
        self.password = password
        self.followers = []
        self.following = []
        self.posts = []

class Product:
    def __init__(self, product_id, name, brand, price, size, color, availability):
        self.product_id = product_id
        self.name = name
        self.brand = brand
        self.price = price
        self.size = size
        self.color = color
        self.availability = availability

class Like:
    def __init__(self, like_id, user, post, timestamp):
        self.like_id = like_id
        self.user = user
        self.post = post
        self.timestamp = timestamp

class Comment:
    def __init__(self, comment_id, user, post, caption, timestamp):
        self.comment_id = comment_id
        self.user = user
        self.post = post
        self.caption = caption
        self.timestamp = timestamp

class Myntra:
    def __init__(self):
        self.users = {}
        self.products = {}
        self.likes = {}
        self.comments = {}

    def add_user(self, user_id, username, password):
        user = User(user_id, username, password)
        self.users[user_id] = user

    def add_product(self, product_id, name, brand, price, size, color, availability):
        product = Product(product_id, name, brand, price, size, color, availability)
        self.products[product_id] = product

    def follow_user(self, user_id1, user_id2):
        if user_id1 in self.users and user_id2 in self.users:
            self.users[user_id1].following.append(user_id2)
            self.users[user_id2].followers.append(user_id1)

    def unfollow_user(self, user_id1, user_id2):
        if user_id1 in self.users and user_id2 in self.users:
            self.users[user_id1].following.remove(user_id2)
            self.users[user_id2].followers.remove(user_id1)

    def create_post(self, user_id, caption):
        if user_id in self.users:
            user = self.users[user_id]
            post_id = str(uuid.uuid4())
            timestamp = datetime.now()
            post = Post(post_id, user, caption, timestamp)
            self.posts[post_id] = post
            user.posts.append(post_id)

    def like_post(self, user_id, post_id):
        if user_id in self.users and post_id in self.posts:
            user = self.users[user_id]
            post = self.posts[post_id]
            like_id = str(uuid.uuid4())
            timestamp = datetime.now()
            like = Like(like_id, user, post, timestamp)
            self.likes[like_id] = like
            post.likes.append(like_id)

    def comment_post(self, user_id, post_id, caption):
        if user_id in self.users and post_id in self.posts:
            user = self.users[user_id]
            post = self.posts[post_id]
            comment_id = str(uuid.uuid4())
            timestamp = datetime.now()
            comment = Comment(comment_id, user, post, caption, timestamp)
            self.comments[comment_id] = comment
            post.comments.append(comment_id)

from flask import Flask, request, jsonify

app = Flask(__name__)

# Sample data for products
products = [
    {"id": 1, "name": "T-shirt", "brand": "Nike", "price": 25.99, "size": "M", "color": "Blue"},
    {"id": 2, "name": "Jeans", "brand": "Levi's", "price": 49.99, "size": "32", "color": "Black"},
    {"id": 3, "name": "Sneakers", "brand": "Adidas", "price": 74.99, "size": "9", "color": "White"},
]

carts = {}
orders = {}
order_id_counter = 1

@app.route('/api/users', methods=['POST'])
def register_user():
    data = request.json
    user_id = len(carts) + 1
    carts[user_id] = {}
    return jsonify({"message": "User registered successfully!", "user_id": user_id}), 201

@app.route('/api/users/<int:user_id>', methods=['GET'])
def get_user(user_id):
    if user_id in carts:
        return jsonify({"user_id": user_id})
    return jsonify({"message": "User not found"}), 404

@app.route('/api/products', methods=['GET'])
def get_products():
    limit = int(request.args.get('limit', 10))
    offset = int(request.args.get('offset', 0))
    paginated_products = products[offset: offset + limit]
    return jsonify(paginated_products)

@app.route('/api/products/<int:product_id>', methods=['GET'])
def get_product(product_id):
    product = next((p for p in products if p['id'] == product_id), None)
    if product:
        return jsonify(product)
    return jsonify({"message": "Product not found"}), 404

@app.route('/api/search', methods=['GET'])
def search_products():
    keyword = request.args.get('keyword')
    filtered_products = [p for p in products if keyword.lower() in p['name'].lower()]
    return jsonify(filtered_products)

@app.route('/api/cart', methods=['POST'])
def add_to_cart():
    data = request.json
    user_id = data['user_id']
    product_id = data['product_id']
    quantity = data['quantity']

    if user_id not in carts:
        carts[user_id] = {}

    cart = carts[user_id]
    cart[product_id] = cart.get(product_id, 0) + quantity
    return jsonify({"message": "Item added to cart successfully!"}), 201

@app.route('/api/cart', methods=['PUT'])
def update_cart():
    data = request.json
    user_id = data['user_id']
    product_id = data['product_id']
    new_quantity = data['quantity']

    if user_id not in carts or product_id not in carts[user_id]:
        return jsonify({"message": "Item not found in cart"}), 404

    carts[user_id][product_id] = new_quantity
    return jsonify({"message": "Cart updated successfully!"})

@app.route('/api/cart', methods=['DELETE'])
def remove_from_cart():
    data = request.json
    user_id = data['user_id']
    product_id = data['product_id']

    if user_id not in carts or product_id not in carts[user_id]:
        return jsonify({"message": "Item not found in cart"}), 404

    del carts[user_id][product_id]
    return jsonify({"message": "Item removed from cart successfully!"})

@app.route('/api/orders', methods=['POST'])
def place_order():
    data = request.json
    user_id = data['user_id']
    product_ids = data['product_ids']
    quantities = data['quantities']

    global order_id_counter
    order_id = order_id_counter
    order_id_counter += 1

    total_price = 0
    order_details = []
    for pid, qty in zip(product_ids, quantities):
        product = next((p for p in products if p['id'] == pid), None)
        if product:
            item_price = product['price'] * qty
            total_price += item_price
            order_details.append({
                "product_id": pid,
                "product_name": product['name'],
                "quantity": qty,
                "total_price": item_price
            })

    orders[order_id] = {
        "order_id": order_id,
        "user_id": user_id,
        "order_details": order_details,
        "total_price": total_price
    }

    return jsonify({"message": "Order placed successfully!", "order_id": order_id}), 201

@app.route('/api/orders/<int:order_id>', methods=['GET'])
def get_order(order_id):
    order = orders.get(order_id)
    if order:
        return jsonify(order)
    return jsonify({"message": "Order not found"}), 404

if __name__ == '__main__':
    app.run()

User Management API:
Endpoint: /api/users

Functionality:

POST: Register a new user with provided details (name, email, password).
GET: Get the user details by passing user ID in the request headers.

Product Catalog API:
Endpoint: /api/products

Functionality:

GET: Get a list of products with pagination support (limit and offset parameters).
GET: Get product details by passing product ID in the request headers.

Search API:
Endpoint: /api/search

Functionality:

GET: Search for products based on keywords and optional filters (brand, size, color, etc.).

Cart API:
Endpoint: /api/cart

Functionality:

POST: Add items to the user's cart by passing the product ID and quantity.
PUT: Update the quantity of items in the user's cart by passing the product ID and new quantity.
DELETE: Remove items from the user's cart by passing the product ID.

Order API:
Endpoint: /api/orders

Functionality:

POST: Place a new order by passing the product IDs and quantities.
GET: Get the order details by passing the order ID in the request headers.

Payment API:
Endpoint: /api/payments

Functionality:

POST: Process payment for an order by passing the order ID and payment details (credit card info, etc.).

from flask import Flask, request, jsonify

app = Flask(__name__)

# Sample data for products
products = [
    {"id": 1, "name": "T-shirt", "brand": "Nike", "price": 25.99, "size": "M", "color": "Blue", "availability": 10},
    {"id": 2, "name": "Jeans", "brand": "Levi's", "price": 49.99, "size": "32", "color": "Black", "availability": 5},
    {"id": 3, "name": "Sneakers", "brand": "Adidas", "price": 74.99, "size": "9", "color": "White", "availability": 8},
]

# User profiles
users = {}

# Shopping carts
carts = {}

# Orders
orders = {}
order_id_counter = 1

# Product Catalog API
@app.route('/api/products', methods=['GET'])
def get_products():
    limit = int(request.args.get('limit', 10))
    offset = int(request.args.get('offset', 0))
    paginated_products = products[offset: offset + limit]
    return jsonify(paginated_products)

@app.route('/api/products/<int:product_id>', methods=['GET'])
def get_product(product_id):
    product = next((p for p in products if p['id'] == product_id), None)
    if product:
        return jsonify(product)
    return jsonify({"message": "Product not found"}), 404

# User Profiles and Personalization API
@app.route('/api/users', methods=['POST'])
def register_user():
    data = request.json
    user_id = len(users) + 1
    users[user_id] = {
        "name": data['name'],
        "email": data['email'],
        "preferences": {}
    }
    return jsonify({"message": "User registered successfully!", "user_id": user_id}), 201

@app.route('/api/users/<int:user_id>', methods=['GET'])
def get_user(user_id):
    user = users.get(user_id)
    if user:
        return jsonify(user)
    return jsonify({"message": "User not found"}), 404

# Search and Filters API
@app.route('/api/search', methods=['GET'])
def search_products():
    keyword = request.args.get('keyword')
    brand = request.args.get('brand')
    size = request.args.get('size')
    color = request.args.get('color')
    price_min = float(request.args.get('price_min', 0))
    price_max = float(request.args.get('price_max', float('inf')))

    filtered_products = [p for p in products if
                         (not keyword or keyword.lower() in p['name'].lower()) and
                         (not brand or brand.lower() == p['brand'].lower()) and
                         (not size or size == p['size']) and
                         (not color or color.lower() == p['color'].lower()) and
                         (price_min <= p['price'] <= price_max)]

    return jsonify(filtered_products)

# Shopping Cart and Checkout API
@app.route('/api/cart', methods=['POST'])
def add_to_cart():
    data = request.json
    user_id = data['user_id']
    product_id = data['product_id']
    quantity = data['quantity']

    if user_id not in carts:
        carts[user_id] = {}

    cart = carts[user_id]
    cart[product_id] = cart.get(product_id, 0) + quantity
    return jsonify({"message": "Item added to cart successfully!"}), 201

@app.route('/api/cart', methods=['PUT'])
def update_cart():
    data = request.json
    user_id = data['user_id']
    product_id = data['product_id']
    new_quantity = data['quantity']

    if user_id not in carts or product_id not in carts[user_id]:
        return jsonify({"message": "Item not found in cart"}), 404

    carts[user_id][product_id] = new_quantity
    return jsonify({"message": "Cart updated successfully!"})

@app.route('/api/cart', methods=['DELETE'])
def remove_from_cart():
    data = request.json
    user_id = data['user_id']
    product_id = data['product_id']

    if user_id not in carts or product_id not in carts[user_id]:
        return jsonify({"message": "Item not found in cart"}), 404

    del carts[user_id][product_id]
    return jsonify({"message": "Item removed from cart successfully!"})

# Order Management API
@app.route('/api/orders', methods=['POST'])
def place_order():
    data = request.json
    user_id = data['user_id']
    product_ids = data['product_ids']
    quantities = data['quantities']

    global order_id_counter
    order_id = order_id_counter
    order_id_counter += 1

    total_price = 0
    order_details = []
    for pid, qty in zip(product_ids, quantities):
        product = next((p for p in products if p['id'] == pid), None)
        if product:
            if product['availability'] < qty:
                return jsonify({"message": "Insufficient stock for product: {}".format(product['name'])}), 400

            item_price = product['price'] * qty
            total_price += item_price
            order_details.append({
                "product_id": pid,
                "product_name": product['name'],
                "quantity": qty,
                "total_price": item_price
            })
            product['availability'] -= qty

    orders[order_id] = {
        "order_id": order_id,
        "user_id": user_id,
        "order_details": order_details,
        "total_price": total_price
    }

    return jsonify({"message": "Order placed successfully!", "order_id": order_id}), 201

@app.route('/api/orders/<int:order_id>', methods=['GET'])
def get_order(order_id):
    order = orders.get(order_id)
    if order:
        return jsonify(order)
    return jsonify({"message": "Order not found"}), 404

# Payment Gateway Integration API
@app.route('/api/payments', methods=['POST'])
def process_payment():
    data = request.json
    order_id = data['order_id']
    payment_info = data['payment_info']

    order = orders.get(order_id)
    if not order:
        return jsonify({"message": "Order not found"}), 404

    # Payment processing logic here (not implemented in this example)
    # Simulate payment success for demonstration purposes
    order['status'] = 'Paid'
    return jsonify({"message": "Payment processed successfully!"}), 200

if __name__ == '__main__':
    app.run()

User Registration API:

Endpoint: /users/register
Method: POST
Request Payload: { "username": "john_doe", "password": "password123" }
Response: {"message": "User registered successfully", "user_id": "unique_user_id"}

User Login API:

Endpoint: /users/login
Method: POST
Request Payload: { "username": "john_doe", "password": "password123" }
Response: {"message": "Login successful", "user_id": "unique_user_id"}

Follow User API:

Endpoint: /users/{user_id}/follow
Method: POST
Request Payload: {"target_user_id": "user_id_to_follow"}
Response: {"message": "You are now following the user"}

Unfollow User API:

Endpoint: /users/{user_id}/unfollow
Method: POST
Request Payload: {"target_user_id": "user_id_to_unfollow"}
Response: {"message": "You have unfollowed the user"}

Create Post API:

Endpoint: /users/{user_id}/posts
Method: POST
Request Payload: {"caption": "Caption for the post", "image_url": "url_of_the_image"}
Response: {"message": "Post created successfully", "post_id": "unique_post_id"}

Like Post API:

Endpoint: /users/{user_id}/posts/{post_id}/like
Method: POST
Request Payload: {}
Response: {"message": "You liked the post"}

Comment on Post API:

Endpoint: /users/{user_id}/posts/{post_id}/comment
Method: POST
Request Payload: {"comment": "Your comment on the post"}
Response: {"message": "Your comment has been posted"}

Get User Feed API:

Endpoint: /users/{user_id}/feed
Method: GET
Response: {"feed": [{"post_id": "unique_post_id", "caption": "Caption of the post", "image_url": "url_of_the_image", "timestamp": "timestamp_of_the_post"}, ...]}

Get User Profile API:

Endpoint: /users/{user_id}/profile
Method: GET
Response: {"username": "john_doe", "followers": ["follower1", "follower2", ...], "following": ["following1", "following2", ...], "posts": [{"post_id": "unique_post_id", "caption": "Caption of the post", "image_url": "url_of_the_image", "timestamp": "timestamp_of_the_post"}, ...]}

from datetime import datetime
import random

# Sample data (for simulation purposes)
emails_sent = []
emails_received = []
storage_used = 0  # in KB
users = 500_000_000
daily_active_users = 100_000_000

# Simulation for sending emails
def send_email(sender_email, recipient_email, subject, content, attachments=None):
    global storage_used

    # Assume an average email size of 200 KB
    email_size_kb = 200
    storage_used += email_size_kb

    # Store the email (for simulation purposes)
    emails_sent.append({
        'timestamp': datetime.now(),
        'sender_email': sender_email,
        'recipient_email': recipient_email,
        'subject': subject,
        'content': content,
        'attachments': attachments or []
    })

# Simulation for receiving emails
def receive_email(recipient_email):
    global storage_used

    # Simulate 100:1 read to write ratio
    if random.random() < 0.01:
        # Assume an average email size of 200 KB
        email_size_kb = 200
        storage_used += email_size_kb

        # Store the email (for simulation purposes)
        emails_received.append({
            'timestamp': datetime.now(),
            'recipient_email': recipient_email,
            'subject': f"Sample Subject - {len(emails_received)+1}",
            'content': "Sample email content."
        })

# Simulate sending emails for a subset of users (DAU)
for _ in range(daily_active_users):
    sender_email = f"user_{random.randint(1, users)}@outlook.com"
    recipient_email = f"user_{random.randint(1, users)}@outlook.com"
    subject = f"Sample Subject - {len(emails_sent)+1}"
    content = "Sample email content."
    send_email(sender_email, recipient_email, subject, content)

# Simulate receiving emails for a subset of users (DAU)
for _ in range(daily_active_users):
    recipient_email = f"user_{random.randint(1, users)}@outlook.com"
    receive_email(recipient_email)

print("Total storage used (KB):", storage_used)

class User:
    def __init__(self, user_id, username, email, password):
        self.user_id = user_id
        self.username = username
        self.email = email
        self.password = password
        # Other user attributes (e.g., contacts, tasks)

class Email:
    def __init__(self, email_id, sender, recipients, subject, content, timestamp):
        self.email_id = email_id
        self.sender = sender
        self.recipients = recipients
        self.subject = subject
        self.content = content
        self.timestamp = timestamp

class Contact:
    def __init__(self, contact_id, user_id, name, email, phone=None):
        self.contact_id = contact_id
        self.user_id = user_id
        self.name = name
        self.email = email
        self.phone = phone

class Task:
    def __init__(self, task_id, user_id, task_name, description=None, due_date=None):
        self.task_id = task_id
        self.user_id = user_id
        self.task_name = task_name
        self.description = description
        self.due_date = due_date

from flask import Flask, request, jsonify
app = Flask(__name__)

# Sample data to be stored in the server
users = {
    "user1": {
        "username": "JohnDoe",
        "email": "[email protected]",
        "password": "password123",
        # Other user attributes (e.g., contacts, tasks)
        "contacts": [
            {"contact_id": 1, "name": "Jane Smith", "email": "[email protected]"},
            {"contact_id": 2, "name": "Bob Johnson", "email": "[email protected]"}
        ],
        "tasks": [
            {"task_id": 1, "task_name": "Buy groceries", "description": "Milk, eggs, bread", "due_date": "2023-07-25"},
            {"task_id": 2, "task_name": "Finish report", "description": "Project XYZ report", "due_date": "2023-07-28"}
        ]
    }
}

# API endpoint for retrieving user information
@app.route('/users/<username>', methods=['GET'])
def get_user(username):
    if username in users:
        return jsonify(users[username]), 200
    else:
        return "User not found", 404

# API endpoint for creating a new contact
@app.route('/users/<username>/contacts', methods=['POST'])
def create_contact(username):
    if username in users:
        data = request.get_json()
        contact_id = len(users[username]['contacts']) + 1
        new_contact = {"contact_id": contact_id, "name": data["name"], "email": data["email"]}
        users[username]['contacts'].append(new_contact)
        return "Contact created", 200
    else:
        return "User not found", 404

# API endpoint for creating a new task
@app.route('/users/<username>/tasks', methods=['POST'])
def create_task(username):
    if username in users:
        data = request.get_json()
        task_id = len(users[username]['tasks']) + 1
        new_task = {"task_id": task_id, "task_name": data["task_name"], "description": data.get("description"), "due_date": data.get("due_date")}
        users[username]['tasks'].append(new_task)
        return "Task created", 200
    else:
        return "User not found", 404

# API endpoint for retrieving user's tasks
@app.route('/users/<username>/tasks', methods=['GET'])
def get_user_tasks(username):
    if username in users:
        return jsonify(users[username]['tasks']), 200
    else:
        return "User not found", 404

# API endpoint for deleting a task
@app.route('/users/<username>/tasks/<int:task_id>', methods=['DELETE'])
def delete_task(username, task_id):
    if username in users:
        for task in users[username]['tasks']:
            if task["task_id"] == task_id:
                users[username]['tasks'].remove(task)
                return "Task deleted", 200
        return "Task not found", 404
    else:
        return "User not found", 404

if __name__ == '__main__':
    app.run()

Sending Email:

Endpoint: POST /api/send_email
Parameters:
sender_email (string): The email address of the sender.
recipient_email (string): The email address of the recipient.
subject (string): The subject of the email.
content (string): The content of the email.
attachments (list of files): (Optional) Any attachments to be included.
Response:
200 OK: Email sent successfully.
400 Bad Request: Invalid parameters or missing data.

Receiving Email:

Endpoint: GET /api/receive_email
Parameters:
recipient_email (string): The email address of the recipient.
Response:
200 OK: List of received emails.
404 Not Found: No emails found for the recipient.

Fetching Calendar Events:

Endpoint: GET /api/calendar_events
Parameters:
user_id (int): The user ID of the calendar owner.
Response:
200 OK: List of calendar events for the user.
404 Not Found: No calendar events found for the user.

Adding a Contact:

Endpoint: POST /api/add_contact
Parameters:
user_id (int): The user ID to whom the contact will be added.
contact_name (string): The name of the contact.
contact_email (string): The email address of the contact.
contact_phone (string): (Optional) The phone number of the contact.
Response:
200 OK: Contact added successfully.
400 Bad Request: Invalid parameters or missing data.

Creating a Task:

Endpoint: POST /api/create_task
Parameters:
user_id (int): The user ID for whom the task will be created.
task_name (string): The name of the task.
task_description (string): (Optional) Description of the task.
due_date (datetime): (Optional) The due date of the task.
Response:
200 OK: Task created successfully.
400 Bad Request: Invalid parameters or missing data.

from flask import Flask, request, jsonify

app = Flask(__name__)

# Sample data (for demonstration purposes)
emails = []
contacts = []
tasks = []

# API to send an email
@app.route('/api/send_email', methods=['POST'])
def send_email():
    data = request.json
    sender_email = data['sender_email']
    recipient_email = data['recipient_email']
    subject = data['subject']
    content = data['content']
    attachments = data.get('attachments', [])

    # Add email to the list (for demonstration purposes)
    emails.append({
        'sender_email': sender_email,
        'recipient_email': recipient_email,
        'subject': subject,
        'content': content,
        'attachments': attachments
    })

    return jsonify({'message': 'Email sent successfully'})

# API to receive emails for a recipient
@app.route('/api/receive_email', methods=['GET'])
def receive_email():
    recipient_email = request.args.get('recipient_email')

    # Retrieve emails for the recipient (for demonstration purposes)
    received_emails = [email for email in emails if email['recipient_email'] == recipient_email]

    if not received_emails:
        return jsonify({'message': 'No emails found for the recipient'}), 404

    return jsonify(received_emails)

# API to add a contact
@app.route('/api/add_contact', methods=['POST'])
def add_contact():
    data = request.json
    user_id = data['user_id']
    contact_name = data['contact_name']
    contact_email = data['contact_email']
    contact_phone = data.get('contact_phone', None)

    # Add contact to the list (for demonstration purposes)
    contacts.append({
        'user_id': user_id,
        'contact_name': contact_name,
        'contact_email': contact_email,
        'contact_phone': contact_phone
    })

    return jsonify({'message': 'Contact added successfully'})

# API to create a task
@app.route('/api/create_task', methods=['POST'])
def create_task():
    data = request.json
    user_id = data['user_id']
    task_name = data['task_name']
    task_description = data.get('task_description', None)
    due_date = data.get('due_date', None)

    # Create task (for demonstration purposes)
    tasks.append({
        'user_id': user_id,
        'task_name': task_name,
        'task_description': task_description,
        'due_date': due_date
    })

    return jsonify({'message': 'Task created successfully'})

if __name__ == '__main__':
    app.run(debug=True)

from flask import Flask, request, jsonify

app = Flask(__name__)

# Sample data (for demonstration purposes)
emails = []
calendar_events = []
contacts = []
tasks = []
notes_journal = []

# Email Management
@app.route('/api/send_email', methods=['POST'])
def send_email():
    data = request.json
    sender_email = data['sender_email']
    recipient_email = data['recipient_email']
    subject = data['subject']
    content = data['content']
    attachments = data.get('attachments', [])

    # Add email to the list (for demonstration purposes)
    emails.append({
        'sender_email': sender_email,
        'recipient_email': recipient_email,
        'subject': subject,
        'content': content,
        'attachments': attachments
    })

    return jsonify({'message': 'Email sent successfully'})

@app.route('/api/receive_email', methods=['GET'])
def receive_email():
    recipient_email = request.args.get('recipient_email')

    # Retrieve emails for the recipient (for demonstration purposes)
    received_emails = [email for email in emails if email['recipient_email'] == recipient_email]

    if not received_emails:
        return jsonify({'message': 'No emails found for the recipient'}), 404

    return jsonify(received_emails)

# Calendar and Schedule
@app.route('/api/add_calendar_event', methods=['POST'])
def add_calendar_event():
    data = request.json
    user_id = data['user_id']
    event_name = data['event_name']
    event_date = data['event_date']

    # Add calendar event (for demonstration purposes)
    calendar_events.append({
        'user_id': user_id,
        'event_name': event_name,
        'event_date': event_date
    })

    return jsonify({'message': 'Calendar event added successfully'})

@app.route('/api/fetch_calendar_events', methods=['GET'])
def fetch_calendar_events():
    user_id = int(request.args.get('user_id'))

    # Retrieve calendar events for the user (for demonstration purposes)
    user_calendar_events = [event for event in calendar_events if event['user_id'] == user_id]
    return jsonify(user_calendar_events)

# Contacts Management
@app.route('/api/add_contact', methods=['POST'])
def add_contact():
    data = request.json
    user_id = data['user_id']
    contact_name = data['contact_name']
    contact_email = data['contact_email']
    contact_phone = data.get('contact_phone', None)

    # Add contact to the list (for demonstration purposes)
    contacts.append({
        'user_id': user_id,
        'contact_name': contact_name,
        'contact_email': contact_email,
        'contact_phone': contact_phone
    })

    return jsonify({'message': 'Contact added successfully'})

@app.route('/api/fetch_contacts', methods=['GET'])
def fetch_contacts():
    user_id = int(request.args.get('user_id'))

    # Retrieve contacts for the user (for demonstration purposes)
    user_contacts = [contact for contact in contacts if contact['user_id'] == user_id]
    return jsonify(user_contacts)

# Task Organization
@app.route('/api/create_task', methods=['POST'])
def create_task():
    data = request.json
    user_id = data['user_id']
    task_name = data['task_name']
    task_description = data.get('task_description', None)
    due_date = data.get('due_date', None)

    # Create task (for demonstration purposes)
    tasks.append({
        'user_id': user_id,
        'task_name': task_name,
        'task_description': task_description,
        'due_date': due_date
    })

    return jsonify({'message': 'Task created successfully'})

@app.route('/api/fetch_tasks', methods=['GET'])
def fetch_tasks():
    user_id = int(request.args.get('user_id'))

    # Retrieve tasks for the user (for demonstration purposes)
    user_tasks = [task for task in tasks if task['user_id'] == user_id]
    return jsonify(user_tasks)

# Notes and Journal
@app.route('/api/add_note', methods=['POST'])
def add_note():
    data = request.json
    user_id = data['user_id']
    note_title = data['note_title']
    note_content = data['note_content']

    # Add note to the list (for demonstration purposes)
    notes_journal.append({
        'user_id': user_id,
        'note_title': note_title,
        'note_content': note_content
    })

    return jsonify({'message': 'Note added successfully'})

@app.route('/api/fetch_notes', methods=['GET'])
def fetch_notes():
    user_id = int(request.args.get('user_id'))

    # Retrieve notes for the user (for demonstration purposes)
    user_notes = [note for note in notes_journal if note['user_id'] == user_id]
    return jsonify(user_notes)

if __name__ == '__main__':
    app.run(debug=True)

from flask import Flask, request, jsonify

app = Flask(__name__)

# Sample data (for demonstration purposes)
emails = []
contacts = []
calendar_events = []
tasks = []

# API to send an email
@app.route('/api/send_email', methods=['POST'])
def send_email():
    data = request.json
    sender_email = data['sender_email']
    recipient_email = data['recipient_email']
    subject = data['subject']
    content = data['content']
    attachments = data.get('attachments', [])

    # Add email to the list (for demonstration purposes)
    emails.append({
        'sender_email': sender_email,
        'recipient_email': recipient_email,
        'subject': subject,
        'content': content,
        'attachments': attachments
    })

    return jsonify({'message': 'Email sent successfully'})

# API to receive emails for a recipient
@app.route('/api/receive_email', methods=['GET'])
def receive_email():
    recipient_email = request.args.get('recipient_email')

    # Retrieve emails for the recipient (for demonstration purposes)
    received_emails = [email for email in emails if email['recipient_email'] == recipient_email]

    if not received_emails:
        return jsonify({'message': 'No emails found for the recipient'}), 404

    return jsonify(received_emails)

# API to add a contact
@app.route('/api/add_contact', methods=['POST'])
def add_contact():
    data = request.json
    user_id = data['user_id']
    contact_name = data['contact_name']
    contact_email = data['contact_email']
    contact_phone = data.get('contact_phone', None)

    # Add contact to the list (for demonstration purposes)
    contacts.append({
        'user_id': user_id,
        'contact_name': contact_name,
        'contact_email': contact_email,
        'contact_phone': contact_phone
    })

    return jsonify({'message': 'Contact added successfully'})

# API to fetch calendar events for a user
@app.route('/api/calendar_events', methods=['GET'])
def fetch_calendar_events():
    user_id = int(request.args.get('user_id'))

    # Retrieve calendar events for the user (for demonstration purposes)
    user_calendar_events = [event for event in calendar_events if event['user_id'] == user_id]

    return jsonify(user_calendar_events)

# API to create a task
@app.route('/api/create_task', methods=['POST'])
def create_task():
    data = request.json
    user_id = data['user_id']
    task_name = data['task_name']
    task_description = data.get('task_description', None)
    due_date = data.get('due_date', None)

    # Create task (for demonstration purposes)
    tasks.append({
        'user_id': user_id,
        'task_name': task_name,
        'task_description': task_description,
        'due_date': due_date
    })

    return jsonify({'message': 'Task created successfully'})

if __name__ == '__main__':
    app.run(debug=True)