Arrays - Two Sum - https://leetcode.com/problems/two-sum/ - 3Sum - https://leetcode.com/problems/3sum/ - Search in Rotated Sorted Array - https://leetcode.com/problems/search-in-rotated-sorted-array/ - Contains Duplicate - https://leetcode.com/problems/contains-duplicate/ Strings - Valid Parentheses - https://leetcode.com/problems/valid-parentheses/ - Longest Substring Without Repeating Characters - https://leetcode.com/problems/longest-substring-without-repeating-characters/ - Valid Anagram - https://leetcode.com/problems/valid-anagram/ - Group Anagrams - https://leetcode.com/problems/group-anagrams/ - Letter Combinations of Phone Number - https://leetcode.com/problems/letter-combinations-of-a-phone-number/ - Basic Calculator - https://leetcode.com/problems/basic-calculator/ Stacks and Queues - Implement queue using stacks - https://leetcode.com/problems/implement-queue-using-stacks/ Graph - Is Graph Bipartite - https://leetcode.com/problems/is-graph-bipartite/ - Graph Valid Tree - https://leetcode.com/problems/graph-valid-tree/ - Course Schedule - https://leetcode.com/problems/course-schedule/ - Number of Islands - https://leetcode.com/problems/number-of-islands/ - Alien Dictionary - https://leetcode.com/problems/alien-dictionary/ - Reconstruct Itinerary - https://leetcode.com/problems/reconstruct-itinerary/ Linked List - Reverse a Linked List - https://leetcode.com/problems/reverse-linked-list/ - Detect Cycle in a Linked List - https://leetcode.com/problems/linked-list-cycle/ - Merge Two Sorted Lists - https://leetcode.com/problems/merge-two-sorted-lists/ - Rotate List - https://leetcode.com/problems/rotate-list Trees - Maximum Depth of Binary Tree - https://leetcode.com/problems/maximum-depth-of-binary-tree/ - Binary Tree Level Order Traversal - https://leetcode.com/problems/binary-tree-level-order-traversal/ - Serialize and Deserialize Binary Tree - https://leetcode.com/problems/serialize-and-deserialize-binary-tree/ - Construct Binary Tree from Preorder and Inorder Traversal - https://leetcode.com/problems/construct-binary-tree-from-preorder-and-inorder-traversal/ - Binary Search Tree Iterator - https://leetcode.com/problems/binary-search-tree-iterator/ - Lowest Common Ancestor of BST - https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-search-tree/ - Vertical traversal - https://www.geeksforgeeks.org/print-binary-tree-vertical-order/ Random - Non-overlapping Intervals - https://leetcode.com/problems/non-overlapping-intervals/ - LRU Cache - https://leetcode.com/problems/lru-cache/ Dynamic Programming - Partition equal subset sum - https://leetcode.com/problems/partition-equal-subset-sum/ - Coin Change - https://leetcode.com/problems/coin-change/ - Jump Game - https://leetcode.com/problems/jump-game-ii/ - Longest Palindromic Subsequence - https://leetcode.com/problems/longest-palindromic-subsequence/ - Edit Distance - https://leetcode.com/problems/edit-distance/