Leetcode solutions written in Javascript
分类标准
- 重点：必须掌握的题型。通常都有着代表一类题型的解法，或者可以举一反三。
- 提高：难度相对高的题，或者思路巧妙的题，提升自我的目的可以练习。
- 了解：一般是解法很容易想到但是细节繁琐，或者和重点题型的解法重复。
String
重点
| Number | Title | Difficulty |
|---|---|---|
| 9 | Palindrome Number | Easy |
| 14 | Longest Common Prefix | Easy |
| 20 | Valid Parentheses | Easy |
| 38 | Count and Say | Easy |
| 67 | Add Binary | Easy. |
| 125 | Valid Palindrome | Easy |
| 205 | Isomorphic Strings | Easy |
| 344 | Reverse String | Easy |
| 345 | Reverse Vowels of a String | Easy |
| 434 | Number of Segments in a String | Easy |
| 459 | Repeated Substring Pattern | Easy |
| 541 | Reverse String II | Easy |
| 606 | Construct String from Binary Tree | Easy |
| 680 | Valid palindrome II | Easy |
| 686 | Repeated String Match | Easy |
| 696 | Count Binary Substrings | Easy |
| 819 | Most Common Word | Easy |
| 3 | Longest Substring Without Repeating Characters | Medium |
| 5 | Longest Palindromic Substring | Medium |
| 17 | Letter Combinations of a Phone Number | Medium |
| 22 | Generate parentheses | Medium |
| 131 | Palindrome Partitioning | Medium |
| 241 | Different Ways to Add Parentheses | Medium |
| 392 | Is Subsequence | Medium |
| 395 | Longest Substring with At Least K Repeating Character | Medium |
| 647 | Palindromic Substrings | Medium |
提高
| Number | Title | Difficulty |
|---|---|---|
| 30 | Substring with Concatenation of All Words | Hard |
| 32 | Longest Valid Parentheses | Hard |
| 76 | Minimum Window Substring | Hard |
| 115 | Distinct Subsequences | Hard |
| 132 | Palindrome Partitioning II | Hard |
| 301 | Remove Invaild Parentheses | Hard |
| 316 | Remove Duplicate Letters | Hard |
| 336 | Palindrome Pairs | Hard |
了解
| Number | Title | Difficulty |
|---|---|---|
| 13 | Roman To Integer | Easy |
| 28 | Implement strStr() | Easy |
| 58 | Length of Last Word | Easy |
| 168 | Excel Sheet Column Title | Easy |
| 171 | Excel Sheet Column Number | Easy |
| 242 | Valid Anagram | Easy |
| 290 | Word Pattern | Easy |
| 383 | Ransom Note | Easy |
| 387 | First Unique Character in a String | Easy |
| 520 | Detect Capital | Easy |
| 557 | Reverse Words in a String III | Easy |
| 657 | Robot Return to origin | Easy |
| 788 | Rotated Digits | Easy |
| 804 | Unique Morse Code Words | Easy |
| 12 | Integer to Roman | Medium |
| 49 | Group Anagrams | Medium |
| 151 | Reverse Words in a String | Medium |
| 537 | Complex Number Multiplication | Medium |
| 791 | Custom Sort String | Medium |
Array
重点
提高
| Number | Title | Difficulty |
|---|---|---|
| 11 | Container With Most Water | Medium |
| 289 | Game of Life | Medium |
| 299 | Bulls and Cows | Medium |
| 309 | Best Time to Buy and Sell Stock with Cooldown | Medium |
| 376 | Wiggle Subsequence | Medium |
| 42 | Trapping Rain Water | Hard |
| 123 | Best Time to Buy and Sell Stock III | Hard |
| 164 | Maximum Gap | Hard |
| 188 | Best Time to Buy and Sell Stock IV | Hard |
了解
| Number | Title | Diffuculty |
|---|---|---|
| 66 | Plus One | Easy |
| 169 | Majority Element | Easy |
| 485 | Max Consecutive Ones | Easy |
| 561 | Array Partition I | Easy |
| 661 | Image Smoother | Easy |
| 747 | Largest Number At Least Twice of Others | Easy |
| 80 | Remove Duplicates from Sorted Array II | Medium |
| 228 | Summary Ranges | Medium |
| 274 | H-Index | Medium |
Stack
重点
| Number | Title | Difficulty |
|---|---|---|
| 225 | Implement Stack using Queues | Easy |
| 232 | Implement Queue using Stacks | Easy |
| 71 | Simplify Path | Medium |
| 150 | Evaluate Reverse Polish Notation | Medium |
| 215 | Kth Largest Element in an Array | Medium |
| 227 | Basic Calculator | Medium |
| 347 | Top K Frequent Elements | Medium |
| 394 | Decode String | Medium |
| 402 | Remove K Digits | Medium |
| 503 | Next Greater Element II | Medium |
| 739 | Daily Temperatures | Medium |
| 224 | Basic Calculator | Hard |
提高
| Number | Title | Difficulty |
|---|---|---|
| 332 | Reconstruct Ltinerary | Medium |
| 388 | Longest Absolute File Path | Medium |
| 84 | Largest Rectangle in Histogram | Hard |
了解
| Number | Title | Difficulty |
|---|---|---|
| 155 | Min Stack | Easy |
| 341 | Flatten Nested list Iterator | Medium |
| 682 | Baseball Game | Medium |
LinkedList
重点
| Number | Title | Difficulty |
|---|---|---|
| 21 | Merge Two Sorted Lists | Easy |
| 83 | Remove Duplicates from Sorted List | Easy |
| 141 | Linked List Cycle | Easy |
| 160 | Intersection of Two Linked Lists | Easy |
| 203 | Remove Linked List Elements | Easy |
| 206 | Reverse Linked List | Easy |
| 234 | Palindrome Linked List | Easy |
| 237 | Delete Node in a Linked List | Easy |
| 2 | Add Two Numbers | Medium |
| 19 | Remove Nth Node From End of List | Medium |
| 24 | Swap Nodes in Pairs | Medium |
| 61 | Rotate List | Medium |
| 86 | Partition List | Medium |
| 142 | Linked List Cycle II | Medium |
| 147 | Insertion Sort List | Medium |
| 148 | Sort List | Medium |
| 328 | Odd Even Linked List | Medium |
| 817 | Linked List Components | Medium |
| 23 | Merge k Sorted List | Hard |
了解
| Number | Title | Difficulty |
|---|---|---|
| 82 | Remove Duplicates from Sorted List II | Medium |
| 92 | Reverse Linked List | Medium |
| 143 | Reorder List | Medium |
| 25 | Reverse Nodes in k-Group | Hard |
Tree
重点
| Number | Title | Difficulty |
|---|---|---|
| 100 | Same Tree | Easy |
| 101 | Symmetric Tree | Easy |
| 104 | Maximum Depth of Binary Tree | Easy |
| 107 | Binary Tree Level Order Traversal II | Easy |
| 108 | Convert Sorted Array to Binary Search Tree | Easy |
| 110 | Balanced Binary Tree | Easy |
| 111 | Minimum Depth of Binary Tree | Easy |
| 112 | Path Sum | Easy |
| 226 | invert Binary Tree | Easy |
| 235 | Lowest Common Ancestor of a Binary Search Tree | Easy |
| 257 | Binary Tree Paths | Easy |
| 94 | Binary Tree Inorder Traversal | Medium |
| 96 | Unique Binary Search Trees | Medium |
| 98 | Validate Binary Search Tree | Medium |
| 109 | Convert Sorted List to Binary Search Tree | Medium |
| 116 | Populating Next Right Pointers in Each Node | Medium |
| 129 | Sum Root to Leaf Numbers | Medium |
| 144 | Binary Tree Preorder Traversal | Medium |
| 230 | Kth Smallest Element in a BST | Medium |
| 236 | Lowest Common Ancestor of a Binary Tree | Medium |
| 99 | Recover Binary Search Tree | Hard |
| 124 | Binary Tree Maximum Path Sum | Hard |
| 145 | Binary Tree Postorder Traversal | Hard |
| 297 | Serialize and Deserialize Binary Tree | Hard |
提高
| Number | Title | Difficulty |
|---|---|---|
| 337 | House Robber III | Middle |
了解
| Number | Title | Difficulty |
|---|---|---|
| 102 | Binary Tree Level Order Traversal | Medium |
| 103 | Binary Tree Zigzag Level Order Traversal | Medium |
| 113 | Path Sum II | Medium |
| 173 | Binary Search Tree Iterator | Medium |
| 199 | Binary Tree Right Side View | Medium |
Binary Search
重点
| Number | Title | Difficulty |
|---|---|---|
| 35 | Search Insert Position | Easy |
| 33 | Search in Rotated Sorted Array | Medium |
| 315 | Count of Smaller Nunmbers After Self | Hard |
了解
| Number | Title | Difficulty |
|---|---|---|
| 278 | First Bad Version | Easy |
| 34 | Find First and Last Position of Element in Sorted Array | Medium |
| 81 | Search in Rotated Sorted Array II | Medium |
| 162 | Find Peak Element | Medium |
Backtracking
重点
| Number | Title | Difficulty |
|---|---|---|
| 39 | Combination Sum | Medium |
| 40 | Combination Sum II | Medium |
| 46 | Permutations | Medium |
| 47 | Permutations II | Medium |
了解
| Number | Title | Difficulty |
|---|---|---|
| 77 | Combinations | Medium |
| 78 | Subsets | Medium |
| 90 | Subsets II | Medium |
| 216 | Combination Sum III | Medium |
Dynamic Programming
重点
| Number | Title | Difficulty |
|---|---|---|
| 70 | Climbing Stairs | Easy |
| 198 | House Robber | Easy |
| 62 | Unique Path | Medium |
| 63 | Unique Path | Medium |
| 64 | Minimum Path Sum | Medium |
| 91 | Decode Ways | Medium |
| 120 | Triangle | Medium |
| 139 | Word Break | Medium |
| 221 | Maximal Square | Medium |
| 279 | Perfect Squares | Medium |
了解
| Number | Title | Difficulty |
|---|---|---|
| 322 | Coin Change | Medium |