https://www.techinterviewhandbook.org/grind75
| Week | No | Question Title | Question URL | Difficulty | Topic | Time |
|---|---|---|---|---|---|---|
| 1 | 1 | Two Sum | https://leetcode.com/problems/two-sum | Easy | Array | 15 mins |
| 1 | 2 | Valid Parentheses | https://leetcode.com/problems/valid-parentheses | Easy | Stack | 20 mins |
| 1 | 3 | Merge Two Sorted Lists | https://leetcode.com/problems/merge-two-sorted-lists | Easy | Linked List | 20 mins |
| 1 | 4 | Best Time to Buy and Sell Stock | https://leetcode.com/problems/best-time-to-buy-and-sell-stock | Easy | Array | 20 mins |
| 1 | 5 | Valid Palindrome | https://leetcode.com/problems/valid-palindrome | Easy | String | 15 mins |
| 1 | 6 | Invert Binary Tree | https://leetcode.com/problems/invert-binary-tree | Easy | Binary Tree | 15 mins |
| 1 | 7 | Valid Anagram | https://leetcode.com/problems/valid-anagram | Easy | String | 15 mins |
| 1 | 8 | Binary Search | https://leetcode.com/problems/binary-search | Easy | Binary Search | 15 mins |
| 1 | 9 | Flood Fill | https://leetcode.com/problems/flood-fill | Easy | Graph | 20 mins |
| 1 | 10 | Lowest Common Ancestor of a Binary Search Tree | https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-search-tree | Easy | Binary Search Tree | 20 mins |
| 1 | 11 | Balanced Binary Tree | https://leetcode.com/problems/balanced-binary-tree | Easy | Binary Tree | 15 mins |
| 1 | 12 | Linked List Cycle | https://leetcode.com/problems/linked-list-cycle | Easy | Linked List | 20 mins |
| 1 | 13 | Implement Queue using Stacks | https://leetcode.com/problems/implement-queue-using-stacks | Easy | Stack | 20 mins |
| 2 | 1 | First Bad Version | https://leetcode.com/problems/first-bad-version | Easy | Binary Search | 20 mins |
| 2 | 2 | Ransom Note | https://leetcode.com/problems/ransom-note | Easy | Hash Table | 15 mins |
| 2 | 3 | Climbing Stairs | https://leetcode.com/problems/climbing-stairs | Easy | Dynamic Programming | 20 mins |
| 2 | 4 | Longest Palindrome | https://leetcode.com/problems/longest-palindrome | Easy | String | 20 mins |
| 2 | 5 | Reverse Linked List | https://leetcode.com/problems/reverse-linked-list | Easy | Linked List | 20 mins |
| 2 | 6 | Majority Element | https://leetcode.com/problems/majority-element | Easy | Array | 20 mins |
| 2 | 7 | Add Binary | https://leetcode.com/problems/add-binary | Easy | Binary | 15 mins |
| 2 | 8 | Diameter of Binary Tree | https://leetcode.com/problems/diameter-of-binary-tree | Easy | Binary Tree | 30 mins |
| 2 | 9 | Middle of the Linked List | https://leetcode.com/problems/middle-of-the-linked-list | Easy | Linked List | 20 mins |
| 2 | 10 | Maximum Depth of Binary Tree | https://leetcode.com/problems/maximum-depth-of-binary-tree | Easy | Binary Tree | 15 mins |
| 2 | 11 | Contains Duplicate | https://leetcode.com/problems/contains-duplicate | Easy | Array | 15 mins |
| 2 | 12 | Maximum Subarray | https://leetcode.com/problems/maximum-subarray | Medium | Dynamic Programming | 20 mins |
| 3 | 1 | Insert Interval | https://leetcode.com/problems/insert-interval | Medium | Array | 25 mins |
| 3 | 2 | 01 Matrix | https://leetcode.com/problems/01-matrix | Medium | Graph | 30 mins |
| 3 | 3 | K Closest Points to Origin | https://leetcode.com/problems/k-closest-points-to-origin | Medium | Heap | 30 mins |
| 3 | 4 | Longest Substring Without Repeating Characters | https://leetcode.com/problems/longest-substring-without-repeating-characters | Medium | String | 30 mins |
| 3 | 5 | 3Sum | https://leetcode.com/problems/3sum | Medium | Array | 30 mins |
| 3 | 6 | Binary Tree Level Order Traversal | https://leetcode.com/problems/binary-tree-level-order-traversal | Medium | Binary Tree | 20 mins |
| 3 | 7 | Clone Graph | https://leetcode.com/problems/clone-graph | Medium | Graph | 25 mins |
| 3 | 8 | Evaluate Reverse Polish Notation | https://leetcode.com/problems/evaluate-reverse-polish-notation | Medium | Stack | 30 mins |
| 4 | 1 | Course Schedule | https://leetcode.com/problems/course-schedule | Medium | Graph | 30 mins |
| 4 | 2 | Implement Trie (Prefix Tree) | https://leetcode.com/problems/implement-trie-prefix-tree | Medium | Trie | 35 mins |
| 4 | 3 | Coin Change | https://leetcode.com/problems/coin-change | Medium | Dynamic Programming | 25 mins |
| 4 | 4 | Product of Array Except Self | https://leetcode.com/problems/product-of-array-except-self | Medium | Array | 30 mins |
| 4 | 5 | Min Stack | https://leetcode.com/problems/min-stack | Medium | Stack | 20 mins |
| 4 | 6 | Validate Binary Search Tree | https://leetcode.com/problems/validate-binary-search-tree | Medium | Binary Search Tree | 20 mins |
| 4 | 7 | Number of Islands | https://leetcode.com/problems/number-of-islands | Medium | Graph | 25 mins |
| 4 | 8 | Rotting Oranges | https://leetcode.com/problems/rotting-oranges | Medium | Graph | 30 mins |
| 5 | 1 | Search in Rotated Sorted Array | https://leetcode.com/problems/search-in-rotated-sorted-array | Medium | Binary Search | 30 mins |
| 5 | 2 | Combination Sum | https://leetcode.com/problems/combination-sum | Medium | Array | 30 mins |
| 5 | 3 | Permutations | https://leetcode.com/problems/permutations | Medium | Recursion | 30 mins |
| 5 | 4 | Merge Intervals | https://leetcode.com/problems/merge-intervals | Medium | Array | 30 mins |
| 5 | 5 | Lowest Common Ancestor of a Binary Tree | https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-tree | Medium | Binary Tree | 25 mins |
| 5 | 6 | Time Based Key-Value Store | https://leetcode.com/problems/time-based-key-value-store | Medium | Binary Search | 35 mins |
| 5 | 7 | Accounts Merge | https://leetcode.com/problems/accounts-merge | Medium | Graph | 30 mins |
| 5 | 8 | Sort Colors | https://leetcode.com/problems/sort-colors | Medium | Array | 25 mins |
| 6 | 1 | Word Break | https://leetcode.com/problems/word-break | Medium | Trie | 30 mins |
| 6 | 2 | Partition Equal Subset Sum | https://leetcode.com/problems/partition-equal-subset-sum | Medium | Dynamic Programming | 30 mins |
| 6 | 3 | String to Integer (atoi) | https://leetcode.com/problems/string-to-integer-atoi | Medium | String | 25 mins |
| 6 | 4 | Spiral Matrix | https://leetcode.com/problems/spiral-matrix | Medium | Matrix | 25 mins |
| 6 | 5 | Subsets | https://leetcode.com/problems/subsets | Medium | Recursion | 30 mins |
| 6 | 6 | Binary Tree Right Side View | https://leetcode.com/problems/binary-tree-right-side-view | Medium | Binary Tree | 20 mins |
| 6 | 7 | Longest Palindromic Substring | https://leetcode.com/problems/longest-palindromic-substring | Medium | String | 25 mins |
| 6 | 8 | Unique Paths | https://leetcode.com/problems/unique-paths | Medium | Dynamic Programming | 20 mins |
| 6 | 9 | Construct Binary Tree from Preorder and Inorder Traversal | https://leetcode.com/problems/construct-binary-tree-from-preorder-and-inorder-traversal | Medium | Binary Tree | 25 mins |
| 7 | 1 | Container With Most Water | https://leetcode.com/problems/container-with-most-water | Medium | Array | 35 mins |
| 7 | 2 | Letter Combinations of a Phone Number | https://leetcode.com/problems/letter-combinations-of-a-phone-number | Medium | Recursion | 30 mins |
| 7 | 3 | Word Search | https://leetcode.com/problems/word-search | Medium | Graph | 30 mins |
| 7 | 4 | Find All Anagrams in a String | https://leetcode.com/problems/find-all-anagrams-in-a-string | Medium | String | 30 mins |
| 7 | 5 | Minimum Height Trees | https://leetcode.com/problems/minimum-height-trees | Medium | Graph | 30 mins |
| 7 | 6 | Task Scheduler | https://leetcode.com/problems/task-scheduler | Medium | Heap | 35 mins |
| 7 | 7 | LRU Cache | https://leetcode.com/problems/lru-cache | Medium | Linked List | 30 mins |
| 8 | 1 | Kth Smallest Element in a BST | https://leetcode.com/problems/kth-smallest-element-in-a-bst | Medium | Binary Search Tree | 25 mins |
| 8 | 2 | Minimum Window Substring | https://leetcode.com/problems/minimum-window-substring | Hard | String | 30 mins |
| 8 | 3 | Serialize and Deserialize Binary Tree | https://leetcode.com/problems/serialize-and-deserialize-binary-tree | Hard | Binary Tree | 40 mins |
| 8 | 4 | Trapping Rain Water | https://leetcode.com/problems/trapping-rain-water | Hard | Stack | 35 mins |
| 8 | 5 | Find Median from Data Stream | https://leetcode.com/problems/find-median-from-data-stream | Hard | Heap | 30 mins |
| 8 | 6 | Word Ladder | https://leetcode.com/problems/word-ladder | Hard | Graph | 45 mins |
| 8 | 7 | Basic Calculator | https://leetcode.com/problems/basic-calculator | Hard | Stack | 40 mins |
| 8 | 8 | Maximum Profit in Job Scheduling | https://leetcode.com/problems/maximum-profit-in-job-scheduling | Hard | Binary Search | 45 mins |
| 8 | 9 | Merge k Sorted Lists | https://leetcode.com/problems/merge-k-sorted-lists | Hard | Heap | 30 mins |
| 8 | 10 | Largest Rectangle in Histogram | https://leetcode.com/problems/largest-rectangle-in-histogram | Hard | Stack | 35 mins |