Most Popular Coding Questions — Company Wise List : Part 1

Just for practice/reference…

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Here we go —

Uber

• Interval List Intersections (5 times): https://leetcode.com/problems/interval-list-intersections/
• Construct K Palindrome Strings (5 times): https://leetcode.com/problems/construct-k-palindrome-strings/
• Meeting Rooms II (5 times): https://leetcode.com/problems/meeting-rooms-ii/
• Serialize and Deserialize Binary Tree (5 times): https://leetcode.com/problems/serialize-and-deserialize-binary-tree/
• Group Anagrams (5 times): https://leetcode.com/problems/group-anagrams/
• Add Two Numbers (4 times): https://leetcode.com/problems/add-two-numbers/
• Construct Quad Tree (6 times): https://leetcode.com/problems/construct-quad-tree/
• Merge Intervals (6 times): https://leetcode.com/problems/merge-intervals/
• Find First and Last Position of Element in Sorted Array (6 times): https://leetcode.com/problems/find-first-and-last-position-of-element-in-sorted-array/
• Minesweeper (6 times): https://leetcode.com/problems/minesweeper/
• Reverse Linked List (6 times): https://leetcode.com/problems/reverse-linked-list/
• Sliding Puzzle (6 times): https://leetcode.com/problems/sliding-puzzle/
• Word Search II (4 times): https://leetcode.com/problems/word-search-ii/
• Grumpy Bookstore Owner (4 times): https://leetcode.com/problems/grumpy-bookstore-owner/
• Text Justification (12 times): https://leetcode.com/problems/text-justification/
• Two Sum (9 times): https://leetcode.com/problems/two-sum/
• Number of Islands (8 times): https://leetcode.com/problems/number-of-islands/
• LRU Cache (8 times): https://leetcode.com/problems/lru-cache/
• Reconstruct Itinerary (7 times): https://leetcode.com/problems/reconstruct-itinerary/
• Rotate Image (7 times): https://leetcode.com/problems/rotate-image/

Most Popular Dynamic Programming and Memoization Questions

Google

• Count Square Sub-matrices with All Ones (13 times): https://leetcode.com/problems/count-square-submatrices-with-all-ones/
• Meeting Rooms II (12 times): https://leetcode.com/problems/meeting-rooms-ii/
• Insert Interval (12 times): https://leetcode.com/problems/insert-interval/
• Find Duplicate Subtrees (12 times): https://leetcode.com/problems/find-duplicate-subtrees/
• Best Time to Buy and Sell Stock (12 times): https://leetcode.com/problems/best-time-to-buy-and-sell-stock/
• Logger Rate Limiter (24 times): https://leetcode.com/problems/logger-rate-limiter/
• Max Area of Island (20 times): https://leetcode.com/problems/max-area-of-island/
• Car Fleet (16 times): https://leetcode.com/problems/car-fleet/
• Add Two Numbers (13 times): https://leetcode.com/problems/add-two-numbers/
• Longest Increasing Path in a Matrix (13 times): https://leetcode.com/problems/longest-increasing-path-in-a-matrix/
• Max Value of Equation (13 times): https://leetcode.com/problems/max-value-of-equation/
• My Calendar I (13 times): https://leetcode.com/problems/my-calendar-i/
• Merge Intervals (13 times): https://leetcode.com/problems/merge-intervals/
• Path With Minimum Effort (12 times): https://leetcode.com/problems/path-with-minimum-effort/
• Decode String (11 times): https://leetcode.com/problems/decode-string/
• Minimum Difference Between Largest and Smallest Value in Three Moves (11 times): https://leetcode.com/problems/minimum-difference-between-largest-and-smallest-value-in-three-moves/
• Maximum Points You Can Obtain from Cards (38 times): https://leetcode.com/problems/maximum-points-you-can-obtain-from-cards/
• Guess the Word (37 times): https://leetcode.com/problems/guess-the-word/
• Two Sum (29 times): https://leetcode.com/problems/two-sum/
• Employee Importance (25 times): https://leetcode.com/problems/employee-importance/

Goldman Sachs

• String Compression (9 times): https://leetcode.com/problems/string-compression/
• Coin Change (8 times): https://leetcode.com/problems/coin-change/
• Palindromic Substrings (8 times): https://leetcode.com/problems/palindromic-substrings/
• Fraction Addition and Subtraction (7 times): https://leetcode.com/problems/fraction-addition-and-subtraction/
• Knight Probability in Chessboard (6 times): https://leetcode.com/problems/knight-probability-in-chessboard/
• Shortest Subarray with Sum at Least K (6 times): https://leetcode.com/problems/shortest-subarray-with-sum-at-least-k/
• Height Checker (6 times): https://leetcode.com/problems/height-checker/
• Fraction to Recurring Decimal (6 times): https://leetcode.com/problems/fraction-to-recurring-decimal/
• Number of Islands (5 times): https://leetcode.com/problems/number-of-islands/
• High Five (33 times): https://leetcode.com/problems/high-five/
• Trapping Rain Water (30 times): https://leetcode.com/problems/trapping-rain-water/
• Delete and Earn (27 times): https://leetcode.com/problems/delete-and-earn/
• Minimum Size Subarray Sum (18 times): https://leetcode.com/problems/minimum-size-subarray-sum/
• Group Anagrams (18 times): https://leetcode.com/problems/group-anagrams/
• First Unique Character in a String (14 times): https://leetcode.com/problems/first-unique-character-in-a-string/
• Find Pivot Index (13 times): https://leetcode.com/problems/find-pivot-index/
• Median of Two Sorted Arrays (12 times): https://leetcode.com/problems/median-of-two-sorted-arrays/
• Count Number of Teams (12 times): https://leetcode.com/problems/count-number-of-teams/
• Robot Bounded In Circle (29 times): https://leetcode.com/problems/robot-bounded-in-circle/
• Design HashMap (11 times): https://leetcode.com/problems/design-hashmap/

Byte Dance

• Course Schedule (3 times): https://leetcode.com/problems/course-schedule/
• Merge k Sorted Lists (3 times): https://leetcode.com/problems/merge-k-sorted-lists/
• Decode String (3 times): https://leetcode.com/problems/decode-string/
• Similar String Groups (3 times): https://leetcode.com/problems/similar-string-groups/
• Search a 2D Matrix II (3 times): https://leetcode.com/problems/search-a-2d-matrix-ii/
• Basic Calculator (3 times): https://leetcode.com/problems/basic-calculator/
• Subarray Sum Equals K (3 times): https://leetcode.com/problems/subarray-sum-equals-k/
• Meeting Rooms II (5 times): https://leetcode.com/problems/meeting-rooms-ii/
• Happy Number (4 times): https://leetcode.com/problems/happy-number/
• Product of the Last K Numbers (4 times): https://leetcode.com/problems/product-of-the-last-k-numbers/
• Binary Tree Longest Consecutive Sequence (4 times): https://leetcode.com/problems/binary-tree-longest-consecutive-sequence/
• The Maze (4 times): https://leetcode.com/problems/the-maze/
• Merge Intervals (4 times): https://leetcode.com/problems/merge-intervals/
• Maximum Product of Three Numbers (3 times): https://leetcode.com/problems/maximum-product-of-three-numbers/
• Random Pick with Weight (3 times): https://leetcode.com/problems/random-pick-with-weight/
• Palindrome Partitioning (3 times): https://leetcode.com/problems/palindrome-partitioning/
• Subsets (6 times): https://leetcode.com/problems/subsets/
• Number of Atoms (6 times): https://leetcode.com/problems/number-of-atoms/
• Serialize and Deserialize Binary Tree (5 times): https://leetcode.com/problems/serialize-and-deserialize-binary-tree/
• LRU Cache (5 times): https://leetcode.com/problems/Iru-cache/

Doordash

• Design Browser History (6 times): https://leetcode.com/problems/design-browser-history/
• Maximum Profit in Job Scheduling (6 times): https://leetcode.com/problems/maximum-profit-in-job-scheduling/
• Number of Islands (5 times): https://leetcode.com/problems/number-of-islands/
• Valid Sudoku (3 times): https://leetcode.com/problems/valid-sudoku/
• Minimum Knight Moves (3 times): https://leetcode.com/problems/minimum-knight-moves/
• Immediate Food Delivery II (2 times): https://leetcode.com/problems/immediate-food-delivery-ii/
• Number of Subarrays with Bounded Maximum (2 times): https://leetcode.com/problems/number-of-subarrays-with-bounded-maximum/
• Max Area of Island (21 times): https://leetcode.com/problems/max-area-of-island/
• Employee Free Time (18 times): https://leetcode.com/problems/employee-free-time/
• Count All Valid Pickup and Delivery Options (13 times): https://leetcode.com/problems/count-all-valid-pickup-and-delivery-options/
• K Closest Points to Origin (9 times): https://leetcode.com/problems/k-closest-points-to-origin/
• Course Schedule II (9 times): https://leetcode.com/problems/course-schedule-ii/
• Meeting Scheduler (8 times): https://leetcode.com/problems/meeting-scheduler/
• Longest Increasing Path in a Matrix (3 times): https://leetcode.com/problems/longest-increasing-path-in-a-matrix/
• Maximum Performance of a Team (3 times): https://leetcode.com/problems/maximum-performance-of-a-team/
• Course Schedule (2 times): https://leetcode.com/problems/course-schedule/
• Analyze User Website Visit Pattern (2 times): https://leetcode.com/problems/analyze-user-website-visit-pattern/
• Merge Intervals (2 times): https://leetcode.com/problems/merge-intervals/
• Sudoku Solver (7 times): https://leetcode.com/problems/sudoku-solver/

Meta

• Binary Tree Vertical Order Traversal (10 times): https://leetcode.com/problems/binary-tree-vertical-order-traversal/
• Max Consecutive Ones III (10 times): https://leetcode.com/problems/max-consecutive-ones-iii/
• Remove All Adjacent Duplicates in String II (10 times): https://leetcode.com/problems/remove-all-adjacent-duplicates-in-string-ii/
• Diagonal Traverse (9 times): https://leetcode.com/problems/diagonal-traverse/
• Check Completeness of a Binary Tree (9 times): https://leetcode.com/problems/check-completeness-of-a-binary-tree/
• Nested List Weight Sum (9 times): https://leetcode.com/problems/nested-list-weight-sum/
• Permutations (8 times): https://leetcode.com/problems/permutations/
• Course Schedule (8 times): https://leetcode.com/problems/course-schedule/
• Reverse Linked List (8 times): https://leetcode.com/problems/reverse-linked-list/
• Verifying an Alien Dictionary (146 times): https://leetcode.com/problems/verifying-an-alien-dictionary/
• Minimum Remove to Make Valid Parentheses (110 times): https://leetcode.com/problems/minimum-remove-to-make-valid-parentheses/
• K Closest Points to Origin (98 times): https://leetcode.com/problems/k-closest-points-to-origin/
• Product of Array Except Self (87 times): https://leetcode.com/problems/product-of-array-except-self/
• Valid Palindrome II (82 times): https://leetcode.com/problems/valid-palindrome-ii/
• Subarray Sum Equals K (72 times): https://leetcode.com/problems/subarray-sum-equals-k/
• Leftmost Column with at Least a One (63 times): https://leetcode.com/problems/leftmost-column-with-at-least-a-one/ A
• dd Strings (62 times): https://leetcode.com/problems/add-strings/
• Merge Intervals (60 times): https://leetcode.com/problems/merge-intervals/
• Add Binary (47 times): https://leetcode.com/problems/add-binary/
• Binary Tree Maximum Path Sum (46 times): https://leetcode.com/problems/binary-tree-maximum-path-sum/
• Valid Palindrome (43 times): https://leetcode.com/problems/valid-palindrome/
• Kth Largest Element in an Array (42 times): https://leetcode.com/problems/kth-largest-element-in-an-array/
• Dot Product of Two Sparse Vectors (40 times): https://leetcode.com/problems/dot-product-of-two-sparse-vectors/
• Range Sum of BST (39 times): https://leetcode.com/problems/range-sum-of-bst/
• Binary Tree Right Side View (37 times): https://leetcode.com/problems/binary-tree-right-side-view/
• Design Add and Search Words Data Structure (36 times): https://leetcode.com/problems/design-add-and-search-words-data-structure/
• Lowest Common Ancestor of a Binary Tree (30 times): https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-tree/
• Serialize and Deserialize Binary Tree (29 times): https://leetcode.com/problems/serialize-and-deserialize-binary-tree/
• Binary Search Tree Iterator (29 times): https://leetcode.com/problems/binary-search-tree-iterator/
• Alien Dictionary (27 times): https://leetcode.com/problems/alien-dictionary/
• Word Break (27 times): https://leetcode.com/problems/word-break/
• Find First and Last Position of Element in Sorted Array (26 times): https://leetcode.com/problems/find-first-and-last-position-of-element-in-sorted-array/
• Divide Two Integers (26 times): https://leetcode.com/problems/divide-two-integers/
• Continuous Subarray Sum (26 times): https://leetcode.com/problems/continuous-subarray-sum/
• Pow(x, n) (26 times): https://leetcode.com/problems/powx-n/
• Next Permutation (24 times): https://leetcode.com/problems/next-permutation/
• Trapping Rain Water (35 times): https://leetcode.com/problems/trapping-rain-water/
• Merge Sorted Array (33 times): https://leetcode.com/problems/merge-sorted-array/
• First Bad Version (32 times): https://leetcode.com/problems/first-bad-version/
• Diameter of Binary Tree (32 times): https://leetcode.com/problems/diameter-of-binary-tree/
• Random Pick with Weight (31 times): https://leetcode.com/problems/random-pick-with-weight/
• LRU Cache (23 times): https://leetcode.com/problems/lru-cache/
• Convert Binary Search Tree to Sorted Doubly Linked List (22 times): https://leetcode.com/problems/convert-binary-search-tree-to-sorted-doubly-linked-list/
• Integer to English Words (22 times): https://leetcode.com/problems/integer-to-english-words/
• Accounts Merge (22 times): https://leetcode.com/problems/accounts-merge/
• Remove Invalid Parentheses (22 times): https://leetcode.com/problems/remove-invalid-parentheses/
• Merge k Sorted Lists (21 times): https://leetcode.com/problems/merge-k-sorted-lists/
• Task Scheduler (21 times): https://leetcode.com/problems/task-scheduler/
• Interval List Intersections (21 times): https://leetcode.com/problems/interval-list-intersections/
• Squares of a Sorted Array (21 times): https://leetcode.com/problems/squares-of-a-sorted-array/
• Clone Graph (20 times): https://leetcode.com/problems/clone-graph/
• Kth Missing Positive Number (20 times): https://leetcode.com/problems/kth-missing-positive-number/
• Exclusive Time of Functions (20 times): https://leetcode.com/problems/exclusive-time-of-functions/
• Minimum Window Substring (20 times): https://leetcode.com/problems/minimum-window-substring/
• Vertical Order Traversal of a Binary Tree (20 times): https://leetcode.com/problems/vertical-order-traversal-of-a-binary-tree/
• Word Break II (19 times): https://leetcode.com/problems/word-break-ii/
• Lowest Common Ancestor of a Binary Tree III (19 times): https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-tree-iii/
• Move Zeroes (19 times): https://leetcode.com/problems/move-zeroes/
• Buildings With an Ocean View (19 times): https://leetcode.com/problems/buildings-with-an-ocean-view/
• Closest Binary Search Tree Value (18 times): https://leetcode.com/problems/closest-binary-search-tree-value/
• Remove Linked List Elements (18 times): https://leetcode.com/problems/remove-linked-list-elements/
• String to Integer (atoi) (18 times): https://leetcode.com/problems/string-to-integer-atoi/
• All Nodes Distance K in Binary Tree (18 times): https://leetcode.com/problems/all-nodes-distance-k-in-binary-tree/
• Number of Islands (17 times): https://leetcode.com/problems/number-of-islands/
• Regular Expression Matching (17 times): https://leetcode.com/problems/regular-expression-matching/
• Valid Number (17 times): https://leetcode.com/problems/valid-number/
• Longest Substring Without Repeating Characters (17 times): https://leetcode.com/problems/longest-substring-without-repeating-characters/
• Top K Frequent Elements (16 times): https://leetcode.com/problems/top-k-frequent-elements/
• Search in Rotated Sorted Array (16 times): https://leetcode.com/problems/search-in-rotated-sorted-array/
• Making A Large Island (16 times): https://leetcode.com/problems/making-a-large-island/
• 3Sum (15 times): https://leetcode.com/problems/3sum/
• Simplify Path (15 times): https://leetcode.com/problems/simplify-path/
• Group Shifted Strings (15 times): https://leetcode.com/problems/group-shifted-strings/
• Insert into a Sorted Circular Linked List (15 times): https://leetcode.com/problems/insert-into-a-sorted-circular-linked-list/
• Longest Substring with At Most K Distinct Characters (14 times): https://leetcode.com/problems/longest-substring-with-at-most-k-distinct-characters/
• Combination Sum (14 times): https://leetcode.com/problems/combination-sum/
• Read N Characters Given Read4 II — Call multiple times (14 times): https://leetcode.com/problems/read-n-characters-given-read4-ii-call-multiple-times/
• Balance a Binary Search Tree (14 times): https://leetcode.com/problems/balance-a-binary-search-tree/
• Remove All Adjacent Duplicates In String (13 times): https://leetcode.com/problems/remove-all-adjacent-duplicates-in-string/
• Two Sum (13 times): https://leetcode.com/problems/two-sum/ Word Ladder (13 times): https://leetcode.com/problems/word-ladder/
• Max Area of Island (13 times): https://leetcode.com/problems/max-area-of-island/
• Random Pick Index (13 times): https://leetcode.com/problems/random-pick-index/
• Subsets (13 times): https://leetcode.com/problems/subsets/
• Palindrome Permutation (12 times): https://leetcode.com/problems/palindrome-permutation/
• Flatten Nested List Iterator (11 times): https://leetcode.com/problems/flatten-nested-list-iterator/
• Find Peak Element (11 times): https://leetcode.com/problems/find-peak-element/
• Basic Calculator II (11 times): https://leetcode.com/problems/basic-calculator-ii/
• Find Median from Data Stream (10 times): https://leetcode.com/problems/find-median-from-data-stream/
• Shortest Distance from All Buildings (10 times): https://leetcode.com/problems/shortest-distance-from-all-buildings/
• Best Time to Buy and Sell Stock (10 times): https://leetcode.com/problems/best-time-to-buy-and-sell-stock/
• Daily Temperatures (10 times): https://leetcode.com/problems/daily-temperatures/
• Valid Parentheses (10 times): https://leetcode.com/problems/valid-parentheses/
• Minimum Add to Make Parentheses Valid (12 times): https://leetcode.com/problems/minimum-add-to-make-parentheses-valid/
• Remove Nth Node From End of List (12 times): https://leetcode.com/problems/remove-nth-node-from-end-of-list/
• Insert Delete GetRandom O(1) (12 times): https://leetcode.com/problems/insert-delete-getrandom-o1/
• Multiply Strings (12 times): https://leetcode.com/problems/multiply-strings/
• Expression Add Operators (12 times): https://leetcode.com/problems/expression-add-operators/
• Longest Increasing Path in a Matrix (12 times): https://leetcode.com/problems/longest-increasing-path-in-a-matrix/
• Copy List with Random Pointer (12 times): https://leetcode.com/problems/copy-list-with-random-pointer/
• Add Two Numbers (11 times): https://leetcode.com/problems/add-two-numbers/
• Is Graph Bipartite? (11 times): https://leetcode.com/problems/is-graph-bipartite/
• Recyclable and Low Fat Products (11 times): https://leetcode.com/problems/recyclable-and-low-fat-products/
• 3Sum Closest (11 times): https://leetcode.com/problems/3sum-closest/
• Maximum Swap (11 times): https://leetcode.com/problems/maximum-swap/
• Find K Closest Elements (11 times): https://leetcode.com/problems/find-k-closest-elements/
• Longest Common Prefix (10 times): https://leetcode.com/problems/longest-common-prefix/
• Meeting Rooms II (10 times): https://leetcode.com/problems/meeting-rooms-ii/
• Validate Binary Search Tree (10 times): https://leetcode.com/problems/validate-binary-search-tree/
• Palindrome Linked List (8 times): https://leetcode.com/problems/palindrome-linked-list/
• Strobogrammatic Number (8 times): https://leetcode.com/problems/strobogrammatic-number/
• First Missing Positive (8 times): https://leetcode.com/problems/first-missing-positive/
• Construct Binary Tree from String (8 times): https://leetcode.com/problems/construct-binary-tree-from-string/
• Generate Parentheses (8 times): https://leetcode.com/problems/generate-parentheses/
• Median of Two Sorted Arrays (8 times): https://leetcode.com/problems/median-of-two-sorted-arrays/
• Missing Ranges (8 times): https://leetcode.com/problems/missing-ranges/
• Range Sum Query 2D — Immutable (8 times): https://leetcode.com/problems/range-sum-query-2d-immutable/
• Populating Next Right Pointers in Each Node (8 times): https://leetcode.com/problems/populating-next-right-pointers-in-each-node/
• Reverse Integer (8 times): https://leetcode.com/problems/reverse-integer/
• Minimum Cost For Tickets (8 times): https://leetcode.com/problems/minimum-cost-for-tickets/
• Minimum Knight Moves (8 times): https://leetcode.com/problems/minimum-knight-moves/
• Sum Root to Leaf Numbers (8 times): https://leetcode.com/problems/sum-root-to-leaf-numbers/
• Palindromic Substrings (8 times): https://leetcode.com/problems/palindromic-substrings/
• Binary Tree Level Order Traversal (7 times): https://leetcode.com/problems/binary-tree-level-order-traversal/
• Read N Characters Given Read4 (7 times): https://leetcode.com/problems/read-n-characters-given-read4/
• Path Sum (7 times): https://leetcode.com/problems/path-sum/
• Find Pivot Index (7 times): https://leetcode.com/problems/find-pivot-index/
• Intersection of Two Arrays (7 times): https://leetcode.com/problems/intersection-of-two-arrays/
• Can Place Flowers (7 times): https://leetcode.com/problems/can-place-flowers/
• Kth Smallest Element in a Sorted Matrix (7 times): https://leetcode.com/problems/kth-smallest-element-in-a-sorted-matrix/
• Spiral Matrix (5 times): https://leetcode.com/problems/spiral-matrix/
• Smallest Subtree with all the Deepest Nodes (5 times): https://leetcode.com/problems/smallest-subtree-with-all-the-deepest-nodes/
• Intersection of Three Sorted Arrays (5 times): https://leetcode.com/problems/intersection-of-three-sorted-arrays/
• Stickers to Spell Word (5 times): https://leetcode.com/problems/stickers-to-spell-word/
• Count and Say (5 times): https://leetcode.com/problems/count-and-say/
• Maximum Average Subtree (5 times): https://leetcode.com/problems/maximum-average-subtree/
• Word Search (5 times): https://leetcode.com/problems/word-search/
• Valid Palindrome III (5 times): https://leetcode.com/problems/valid-palindrome-iii/
• Partition Equal Subset Sum (5 times): https://leetcode.com/problems/partition-equal-subset-sum/
• First Unique Character in a String (7 times): https://leetcode.com/problems/first-unique-character-in-a-string/
• N-Queens (7 times): https://leetcode.com/problems/n-queens/
• Contiguous Array (6 times): https://leetcode.com/problems/contiguous-array/
• Design Tic-Tac-Toe (6 times): https://leetcode.com/problems/design-tic-tac-toe/
• Binary Tree Paths (6 times): https://leetcode.com/problems/binary-tree-paths/
• Find All Anagrams in a String (6 times): https://leetcode.com/problems/find-all-anagrams-in-a-string/
• Kth Smallest Element in a BST (6 times): https://leetcode.com/problems/kth-smallest-element-in-a-bst/
• Robot Room Cleaner (6 times): https://leetcode.com/problems/robot-room-cleaner/
• Decode Ways (6 times): https://leetcode.com/problems/decode-ways/
• Strobogrammatic Number II (6 times): https://leetcode.com/problems/strobogrammatic-number-ii/
• Backspace String Compare (6 times): https://leetcode.com/problems/backspace-string-compare/
• Find Largest Value in Each Tree Row (6 times): https://leetcode.com/problems/find-largest-value-in-each-tree-row/
• Letter Combinations of a Phone Number (6 times): https://leetcode.com/problems/letter-combinations-of-a-phone-number/
• Design Circular Queue (6 times): https://leetcode.com/problems/design-circular-queue/
• Sort List (6 times): https://leetcode.com/problems/sort-list/
• Island Perimeter (6 times): https://leetcode.com/problems/island-perimeter/
• Path Sum II (6 times): https://leetcode.com/problems/path-sum-ii/
• Monotonic Array (6 times): https://leetcode.com/problems/monotonic-array/
• Container With Most Water (6 times): https://leetcode.com/problems/container-with-most-water/
• Validate Binary Tree Nodes (5 times): https://leetcode.com/problems/validate-binary-tree-nodes/
• Largest BST Subtree (5 times): https://leetcode.com/problems/largest-bst-subtree/
• Number of Connected Components in an Undirected Graph (5 times): https://leetcode.com/problems/number-of-connected-components-in-an-undirected-graph/
• Odd Even Linked List (5 times): https://leetcode.com/problems/odd-even-linked-list/
• Flatten Binary Tree to Linked List (5 times): https://leetcode.com/problems/flatten-binary-tree-to-linked-list/
• Toeplitz Matrix (5 times): https://leetcode.com/problems/toeplitz-matrix/

Citadel

• Count Number of Teams (2 times): https://leetcode.com/problems/count-number-of-teams/
• Design In-Memory File System (2 times): https://leetcode.com/problems/design-in-memory-file-system/
• LFU Cache (2 times): https://leetcode.com/problems/lfu-cache/
• Wildcard Matching (2 times): https://leetcode.com/problems/wildcard-matching/
• Consecutive Numbers Sum (13 times): https://leetcode.com/problems/consecutive-numbers-sum/
• Number of Islands (7 times): https://leetcode.com/problems/number-of-islands/
• Word Ladder (2 times): https://leetcode.com/problems/word-ladder/
• Best Time to Buy and Sell Stock (2 times): https://leetcode.com/problems/best-time-to-buy-and-sell-stock/
• Construct Binary Tree from Preorder and Inorder Traversal (2 times): https://leetcode.com/problems/construct-binary-tree-from-preorder-and-inorder-traversal/
• Sliding Window Maximum (4 times): https://leetcode.com/problems/sliding-window-maximum/
• Expression Add Operators (3 times): https://leetcode.com/problems/expression-add-operators/
• Open the Lock (3 times): https://leetcode.com/problems/open-the-lock/
• Integer Break (2 times): https://leetcode.com/problems/integer-break/

Part 2 of this series :

All the Complete System Design Series Parts —

1. System design basics

2. Horizontal and vertical scaling

3. Load balancing and Message queues

4. High level design and low level design, Consistent Hashing, Monolithic and Microservices architecture

5. Caching, Indexing, Proxies

6. Networking, How Browsers work, Content Network Delivery ( CDN)

7. Database Sharding, CAP Theorem, Database schema Design

8. Concurrency, API, Components + OOP + Abstraction

9. Estimation and Planning, Performance

10. Map Reduce, Patterns and Microservices

11. SQL vs NoSQL and Cloud

12. Most Popular System Design Questions

Github —

For Python Projects —

For complete 60 days of Data Science and ML : Day 1 — Day 60 : Quick Recap of 60 days of Data Science and ML

Follow for more updates. Stay tuned and keep coding!

Advanced SQL Series

Day 1 : SQL Basics and Kick start of Advanced SQL Series

Day 2 : SQL Basics, Query Structure, Built In functions Conditions

Day 3 : Most Important Commands, Joins and Filters

Day 4 : Set Theory Operations, Stored Procedures and CASE statements in SQL

Day 5 : Wildcards, Aggregation and Sequences in SQL

Day 6 : Subqueries, Group by, order by and Having clauses in SQL and Analytical Functions

Day 7 : Window Functions, Grouping Sets and Constraints in SQL

Day 8 : BigQuery Basics, SELECT, FROM, WHERE and Date and Extract in BigQuery

Day 9 : Common Expression Table, UNNEST Clause, SQL vs NoSQL Databases

Day 10 : Triggers, Pivot and Cursors in SQL

Day 11 : Views, Indexes and Auto Increment in SQL

Day 12 : Query optimizations, Performance tuning in SQL

Day 13 : Introduction to MySQL, PostgreSQL and Mongo DB, Comparison between MySQL and PostgreSQL and Mongo DB, Introduction to SQL and NoSQL Databases

Day 14 : MySQL in Depth

Day 15 : PostgreSQL inDepth

Anyways, For Day 15 of 15 days of Advanced SQL, we will cover —

PostgreSQL inDepth

Github for Advanced SQL that you can follow —

All the projects, data structures, algorithms, system design, Data Science and ML, Data Engineering, MLOps and Deep Learning videos will be published on our youtube channel ( just launched).

Subscribe today!

System Design Case Studies — In Depth

Design Instagram

Design Messenger App

Design Twitter

Design URL Shortener

Design Dropbox

Design Youtube

Design API Rate Limiter

Design Web Crawler

Design Facebook’s Newsfeed

Design Yelp

Design Uber

Design Tinder

Design Tiktok

Design Whatsapp

Most Popular System Design Questions

Mega Compilation : Solved System Design Case studies

Complete Data Structures and Algorithm Series

Complexity Analysis

Backtracking

Sliding Window

Greedy Technique

Two pointer Technique

Arrays

Linked List

Strings

Stack

Queues

Hash Table/Hashing

Binary Search

1- D Dynamic Programming

Divide and Conquer Technique

Recursion

Github —

For other projects, tune to —

Build Machine Learning Pipelines( With Code)

Recurrent Neural Network with Keras

Clustering Geolocation Data in Python using DBSCAN and K-Means

Facial Expression Recognition using Keras

Hyperparameter Tuning with Keras Tuner

Custom Layers in Keras