15.5 Lookup by Study Plan
15.5.1 Blind 75
## *Progress: 60 / 75 problems.*| Platform | ID | Problem | Difficulty | Chapter |
|---|---|---|---|---|
| LeetCode | 1 | Two Sums I | Easy | Array |
| LeetCode | 2 | Add Two Numbers | Medium | Linked List |
| LeetCode | 3 | Longest Substring Without Repeating | Medium | String Manipulation |
| LeetCode | 5 | Longest Palindromic Substring | Medium | Dynamic Programming and Backtracking |
| LeetCode | 11 | Container With Most Water | Medium | Array |
| LeetCode | 15 | 3Sum | Medium | Array |
| LeetCode | 19 | Remove Nth Node From End | Medium | Linked List |
| LeetCode | 21 | Merge Two Sorted Lists | Easy | Linked List |
| LeetCode | 23 | Merge k Sorted Lists | Hard | Linked List |
| LeetCode | 33 | Search in Rotated Sorted Array | Medium | Array |
| LeetCode | 39 | Combination Sum | Medium | Dynamic Programming and Backtracking |
| LeetCode | 48 | Rotate Image | Medium | Matrix |
| LeetCode | 49 | Group Anagrams | Medium | String Manipulation |
| LeetCode | 53 | Maximum Subarray | Easy | Array |
| LeetCode | 54 | Spiral Matrix | Medium | Matrix |
| LeetCode | 56 | Merge Intervals | Medium | Array |
| LeetCode | 57 | Insert Interval | Hard | Array |
| LeetCode | 62 | Unique Paths | Medium | Dynamic Programming and Backtracking |
| LeetCode | 70 | Climbing Stairs | Easy | Dynamic Programming and Backtracking |
| LeetCode | 73 | Set Matrix Zeroes | Medium | Matrix |
| LeetCode | 78 | Subsets | Medium | Dynamic Programming and Backtracking |
| LeetCode | 79 | Word Search | Medium | Dynamic Programming and Backtracking |
| LeetCode | 91 | Decode Ways | Medium | Dynamic Programming and Backtracking |
| LeetCode | 98 | Validate Binary Search Tree | Medium | Tree |
| LeetCode | 102 | Binary Tree Level Order Traversal | Medium | Tree |
| LeetCode | 121 | Best Time to Buy and Sell Stock | Easy | Array |
| LeetCode | 133 | Clone Graph | Medium | Graph |
| LeetCode | 139 | Word Break | Medium | Dynamic Programming and Backtracking |
| LeetCode | 141 | Linked List Cycle | Easy | Linked List |
| LeetCode | 143 | Reorder List | Medium | Linked List |
| LeetCode | 146 | Design LRU Cache | Medium | Advanced Data Structure |
| LeetCode | 152 | Maximum Product Subarray | Medium | Array |
| LeetCode | 155 | Min Stack | Medium | Stack and Queue |
| LeetCode | 190 | Reverse Bits | Easy | Math |
| LeetCode | 198 | House Robber | Easy | Dynamic Programming and Backtracking |
| LeetCode | 200 | Number of Islands | Medium | Matrix |
| LeetCode | 206 | Reverse Linked List | Easy | Linked List |
| LeetCode | 207 | Course Schedule | Medium | Graph |
| LeetCode | 208 | Implement Trie (Prefix Tree) | Medium | Tree |
| LeetCode | 211 | Design Add and Search Words Data Structure | Medium | String Manipulation |
| LeetCode | 215 | Find kth Largest Element | Medium | Heap |
| LeetCode | 230 | Kth Smallest Element in a BST | Medium | Tree |
| LeetCode | 235 | Lowest Common Ancestor of a Binary Search Tree | Medium | Tree |
| LeetCode | 236 | Lowest Common Ancestor of a Binary Tree | Medium | Tree |
| LeetCode | 238 | Product of Array Except Self | Medium | Array |
| LeetCode | 253 | Meeting Rooms II | Medium | Heap |
| LeetCode | 261 | Graph Valid Tree | Medium | Graph |
| LeetCode | 269 | Alien Dictionary | Hard | Graph |
| LeetCode | 271 | Encode and Decode Strings | Medium | String Manipulation |
| LeetCode | 295 | Find Median from Data Stream | Hard | Heap |
| LeetCode | 300 | Longest Increasing Subsequence | Medium | Dynamic Programming and Backtracking |
| LeetCode | 322 | Coin Change | Medium | Dynamic Programming and Backtracking |
| LeetCode | 323 | Number of Connected Components in an Undirected Graph | Medium | Graph |
| LeetCode | 347 | Top K Frequent Elements | Medium | Heap |
| LeetCode | 371 | Sum of Two Integers | Medium | Math |
| LeetCode | 417 | Pacific Atlantic Water Flow | Medium | Matrix |
| LeetCode | 435 | Non-overlapping Intervals | Medium | Array |
| LeetCode | 543 | Diameter of Binary Tree | Easy | Tree |
| LeetCode | 572 | Subtree of Another Tree | Easy | Tree |
| LeetCode | 647 | Palindromic Substrings | Medium | Dynamic Programming and Backtracking |
15.5.2 NeetCode 150
## *Progress: 104 / 150 problems.*| Platform | ID | Problem | Difficulty | Chapter |
|---|---|---|---|---|
| LeetCode | 1 | Two Sums I | Easy | Array |
| LeetCode | 2 | Add Two Numbers | Medium | Linked List |
| LeetCode | 3 | Longest Substring Without Repeating | Medium | String Manipulation |
| LeetCode | 4 | Median of Two Sorted Arrays | Hard | Array |
| LeetCode | 5 | Longest Palindromic Substring | Medium | Dynamic Programming and Backtracking |
| LeetCode | 7 | Reverse Integer | Medium | Math |
| LeetCode | 11 | Container With Most Water | Medium | Array |
| LeetCode | 15 | 3Sum | Medium | Array |
| LeetCode | 17 | Letter Combinations of a Phone Number | Medium | Dynamic Programming and Backtracking |
| LeetCode | 19 | Remove Nth Node From End | Medium | Linked List |
| LeetCode | 21 | Merge Two Sorted Lists | Easy | Linked List |
| LeetCode | 23 | Merge k Sorted Lists | Hard | Linked List |
| LeetCode | 25 | Reverse Nodes in k-Group | Hard | Linked List |
| LeetCode | 26 | Remove Duplicates from Sorted Array | Easy | Array |
| LeetCode | 33 | Search in Rotated Sorted Array | Medium | Array |
| LeetCode | 36 | Valid Sudoku | Medium | Matrix |
| LeetCode | 39 | Combination Sum | Medium | Dynamic Programming and Backtracking |
| LeetCode | 46 | Permutations | Medium | Dynamic Programming and Backtracking |
| LeetCode | 47 | Permutations II | Medium | Dynamic Programming and Backtracking |
| LeetCode | 48 | Rotate Image | Medium | Matrix |
| LeetCode | 49 | Group Anagrams | Medium | String Manipulation |
| LeetCode | 50 | Pow(x; n) | Medium | Math |
| LeetCode | 53 | Maximum Subarray | Easy | Array |
| LeetCode | 54 | Spiral Matrix | Medium | Matrix |
| LeetCode | 56 | Merge Intervals | Medium | Array |
| LeetCode | 57 | Insert Interval | Hard | Array |
| LeetCode | 62 | Unique Paths | Medium | Dynamic Programming and Backtracking |
| LeetCode | 66 | Plus One | Easy | Array |
| LeetCode | 70 | Climbing Stairs | Easy | Dynamic Programming and Backtracking |
| LeetCode | 73 | Set Matrix Zeroes | Medium | Matrix |
| LeetCode | 74 | Search a 2D Matrix | Medium | Matrix |
| LeetCode | 78 | Subsets | Medium | Dynamic Programming and Backtracking |
| LeetCode | 79 | Word Search | Medium | Dynamic Programming and Backtracking |
| LeetCode | 90 | Subsets II | Medium | Dynamic Programming and Backtracking |
| LeetCode | 91 | Decode Ways | Medium | Dynamic Programming and Backtracking |
| LeetCode | 98 | Validate Binary Search Tree | Medium | Tree |
| LeetCode | 102 | Binary Tree Level Order Traversal | Medium | Tree |
| LeetCode | 110 | Balanced Binary Tree | Easy | Tree |
| LeetCode | 121 | Best Time to Buy and Sell Stock | Easy | Array |
| LeetCode | 127 | Word Ladder | Medium | String Manipulation |
| LeetCode | 130 | Surrounded Regions | Medium | Matrix |
| LeetCode | 133 | Clone Graph | Medium | Graph |
| LeetCode | 134 | Gas Station | Medium | Array |
| LeetCode | 136 | Single Number | Easy | Math |
| LeetCode | 138 | Copy List with Random Pointer | Medium | Linked List |
| LeetCode | 139 | Word Break | Medium | Dynamic Programming and Backtracking |
| LeetCode | 141 | Linked List Cycle | Easy | Linked List |
| LeetCode | 143 | Reorder List | Medium | Linked List |
| LeetCode | 146 | Design LRU Cache | Medium | Advanced Data Structure |
| LeetCode | 152 | Maximum Product Subarray | Medium | Array |
| LeetCode | 155 | Min Stack | Medium | Stack and Queue |
| LeetCode | 167 | Two Sum II - Sorted Array | Medium | Array |
| LeetCode | 190 | Reverse Bits | Easy | Math |
| LeetCode | 191 | Number of 1 Bits | Easy | Math |
| LeetCode | 198 | House Robber | Easy | Dynamic Programming and Backtracking |
| LeetCode | 200 | Number of Islands | Medium | Matrix |
| LeetCode | 202 | Happy Number | Easy | Math |
| LeetCode | 206 | Reverse Linked List | Easy | Linked List |
| LeetCode | 207 | Course Schedule | Medium | Graph |
| LeetCode | 208 | Implement Trie (Prefix Tree) | Medium | Tree |
| LeetCode | 209 | Minimum Size Subarray Sum | Medium | Array |
| LeetCode | 210 | Course Schedule II | Medium | Graph |
| LeetCode | 211 | Design Add and Search Words Data Structure | Medium | String Manipulation |
| LeetCode | 215 | Find kth Largest Element | Medium | Heap |
| LeetCode | 230 | Kth Smallest Element in a BST | Medium | Tree |
| LeetCode | 235 | Lowest Common Ancestor of a Binary Search Tree | Medium | Tree |
| LeetCode | 236 | Lowest Common Ancestor of a Binary Tree | Medium | Tree |
| LeetCode | 238 | Product of Array Except Self | Medium | Array |
| LeetCode | 253 | Meeting Rooms II | Medium | Heap |
| LeetCode | 261 | Graph Valid Tree | Medium | Graph |
| LeetCode | 269 | Alien Dictionary | Hard | Graph |
| LeetCode | 271 | Encode and Decode Strings | Medium | String Manipulation |
| LeetCode | 286 | Walls and Gates | Medium | Matrix |
| LeetCode | 287 | Find the Duplicate Number | Medium | Array |
| LeetCode | 295 | Find Median from Data Stream | Hard | Heap |
| LeetCode | 300 | Longest Increasing Subsequence | Medium | Dynamic Programming and Backtracking |
| LeetCode | 309 | Best Time to Buy and Sell Stock with Cooldown | Medium | Dynamic Programming and Backtracking |
| LeetCode | 322 | Coin Change | Medium | Dynamic Programming and Backtracking |
| LeetCode | 323 | Number of Connected Components in an Undirected Graph | Medium | Graph |
| LeetCode | 347 | Top K Frequent Elements | Medium | Heap |
| LeetCode | 355 | Design Twitter | Medium | Advanced Data Structure |
| LeetCode | 371 | Sum of Two Integers | Medium | Math |
| LeetCode | 417 | Pacific Atlantic Water Flow | Medium | Matrix |
| LeetCode | 424 | Longest Repeating Character Replacement | Medium | String Manipulation |
| LeetCode | 435 | Non-overlapping Intervals | Medium | Array |
| LeetCode | 518 | Coin Change II | Medium | Dynamic Programming and Backtracking |
| LeetCode | 543 | Diameter of Binary Tree | Easy | Tree |
| LeetCode | 567 | Permutation in String | Medium | String Manipulation |
| LeetCode | 572 | Subtree of Another Tree | Easy | Tree |
| LeetCode | 621 | Task Scheduler | Medium | Stack and Queue |
| LeetCode | 647 | Palindromic Substrings | Medium | Dynamic Programming and Backtracking |
| LeetCode | 704 | Binary Search | Easy | Array |
| LeetCode | 739 | Daily Temperatures | Medium | Stack and Queue |
| LeetCode | 743 | Network Delay Time | Medium | Graph |
| LeetCode | 846 | Hand of Straights | Medium | Array |
| LeetCode | 853 | Car Fleet | Medium | Stack and Queue |
| LeetCode | 875 | Koko Eating Bananas | Medium | Array |
| LeetCode | 973 | K Closest Points to Origin | Medium | Heap |
| LeetCode | 981 | Time Based Key-Value Store | Medium | Advanced Data Structure |
| LeetCode | 994 | Rotting Oranges | Medium | Matrix |
| LeetCode | 1046 | Last Stone Weight | Easy | Heap |
| LeetCode | 1448 | Count Good Nodes in Binary Tree | Medium | Tree |
| LeetCode | 1899 | Merge Triplets to Form Target Triplet | Medium | Array |
| LeetCode | 2013 | Detect Squares | Medium | Matrix |
15.5.3 Grind 75
## *Progress: 54 / 75 problems.*| Platform | ID | Problem | Difficulty | Chapter |
|---|---|---|---|---|
| LeetCode | 1 | Two Sums I | Easy | Array |
| LeetCode | 3 | Longest Substring Without Repeating | Medium | String Manipulation |
| LeetCode | 5 | Longest Palindromic Substring | Medium | Dynamic Programming and Backtracking |
| LeetCode | 11 | Container With Most Water | Medium | Array |
| LeetCode | 15 | 3Sum | Medium | Array |
| LeetCode | 17 | Letter Combinations of a Phone Number | Medium | Dynamic Programming and Backtracking |
| LeetCode | 21 | Merge Two Sorted Lists | Easy | Linked List |
| LeetCode | 23 | Merge k Sorted Lists | Hard | Linked List |
| LeetCode | 33 | Search in Rotated Sorted Array | Medium | Array |
| LeetCode | 39 | Combination Sum | Medium | Dynamic Programming and Backtracking |
| LeetCode | 46 | Permutations | Medium | Dynamic Programming and Backtracking |
| LeetCode | 53 | Maximum Subarray | Easy | Array |
| LeetCode | 54 | Spiral Matrix | Medium | Matrix |
| LeetCode | 56 | Merge Intervals | Medium | Array |
| LeetCode | 57 | Insert Interval | Hard | Array |
| LeetCode | 62 | Unique Paths | Medium | Dynamic Programming and Backtracking |
| LeetCode | 70 | Climbing Stairs | Easy | Dynamic Programming and Backtracking |
| LeetCode | 73 | Set Matrix Zeroes | Medium | Matrix |
| LeetCode | 75 | Sort Colors | Medium | Array |
| LeetCode | 78 | Subsets | Medium | Dynamic Programming and Backtracking |
| LeetCode | 79 | Word Search | Medium | Dynamic Programming and Backtracking |
| LeetCode | 98 | Validate Binary Search Tree | Medium | Tree |
| LeetCode | 102 | Binary Tree Level Order Traversal | Medium | Tree |
| LeetCode | 110 | Balanced Binary Tree | Easy | Tree |
| LeetCode | 121 | Best Time to Buy and Sell Stock | Easy | Array |
| LeetCode | 127 | Word Ladder | Medium | String Manipulation |
| LeetCode | 133 | Clone Graph | Medium | Graph |
| LeetCode | 136 | Single Number | Easy | Math |
| LeetCode | 139 | Word Break | Medium | Dynamic Programming and Backtracking |
| LeetCode | 141 | Linked List Cycle | Easy | Linked List |
| LeetCode | 146 | Design LRU Cache | Medium | Advanced Data Structure |
| LeetCode | 150 | Evaluate Reverse Polish Notation | Medium | Stack and Queue |
| LeetCode | 155 | Min Stack | Medium | Stack and Queue |
| LeetCode | 190 | Reverse Bits | Easy | Math |
| LeetCode | 200 | Number of Islands | Medium | Matrix |
| LeetCode | 206 | Reverse Linked List | Easy | Linked List |
| LeetCode | 207 | Course Schedule | Medium | Graph |
| LeetCode | 208 | Implement Trie (Prefix Tree) | Medium | Tree |
| LeetCode | 230 | Kth Smallest Element in a BST | Medium | Tree |
| LeetCode | 232 | Implement Queue using Stacks | Easy | Stack and Queue |
| LeetCode | 235 | Lowest Common Ancestor of a Binary Search Tree | Medium | Tree |
| LeetCode | 236 | Lowest Common Ancestor of a Binary Tree | Medium | Tree |
| LeetCode | 238 | Product of Array Except Self | Medium | Array |
| LeetCode | 278 | First Bad Version | Easy | Interactive |
| LeetCode | 322 | Coin Change | Medium | Dynamic Programming and Backtracking |
| LeetCode | 383 | Ransom Note | Easy | String Manipulation |
| LeetCode | 438 | Find All Anagrams in a String | Medium | String Manipulation |
| LeetCode | 543 | Diameter of Binary Tree | Easy | Tree |
| LeetCode | 621 | Task Scheduler | Medium | Stack and Queue |
| LeetCode | 704 | Binary Search | Easy | Array |
| LeetCode | 721 | Accounts Merge | Medium | Graph |
| LeetCode | 973 | K Closest Points to Origin | Medium | Heap |
| LeetCode | 981 | Time Based Key-Value Store | Medium | Advanced Data Structure |
| LeetCode | 994 | Rotting Oranges | Medium | Matrix |