| 1 | Two Sum 两数之和 (opens new window) | Easy |
| 2 | Add Two Numbers 两数相加 (opens new window) | Medium |
| 3 | Longest Substring Without Repeating Characters 无重复字符的最长子串 (opens new window) | Medium |
| 4 | Median of Two Sorted Arrays 两个排序数组的中位数 (opens new window) | Hard |
| 5 | Longest Palindromic Substring 最长回文子串 (opens new window) | Medium |
| 6 | ZigZag Converesion Z 字形变换 (opens new window) | Medium |
| 7 | Reverse Integer 翻转整数 (opens new window) | Easy |
| 8 | String to Integer (atoi) 字符串转为整数 (opens new window) | Medium |
| 9 | Palindrome Number 回文数字 (opens new window) | Easy |
| 10 | Regular Expression Matching 正则表达式匹配 (opens new window) | Hard |
| 11 | Container With Most Water 盛最多水的容器 (opens new window) | Medium |
| 12 | Integer to Roman 整数转罗马数字 (opens new window) | Medium |
| 13 | Roman to Integer 罗马数字转整数 (opens new window) | Easy |
| 14 | Longest Common Prefix 最长共同前缀 (opens new window) | Easy |
| 15 | 3Sum 三数之和 (opens new window) | Medium |
| 16 | 3Sum Closest 最接近的三数之和 (opens new window) | Medium |
| 17 | Letter Combinations of a PhoneNumber 电话号码的字母组合 (opens new window) | Medium |
| 18 | 4Sum 四数之和 (opens new window) | Medium |
| 19 | Remove Nth Node From End of List 删除链表的倒数第 N 个节点 (opens new window) | Medium |
| 20 | Valid Parentheses 有效的括号 (opens new window) | Easy |
| 21 | Merge Two Sorted Lists 合并两个有序链表 (opens new window) | Easy |
| 22 | Generate Parentheses 生成括号 (opens new window) | Medium |
| 23 | Merge k Sorted Lists 合并 K 个排序链表 (opens new window) | Hard |
| 24 | Swap Nodes In Pairs 两两交换链表中的节点 (opens new window) | Medium |
| 25 | Reverse Nodes in k-Group 每 k 个一组翻转链表 (opens new window) | Hard |
| 26 | Remove Duplicates from Sorted Array 从有序数组中删除重复项 (opens new window) | Easy |
| 27 | Remove Element 移除元素 (opens new window) | Easy |
| 28 | Implement strStr() 实现 strStr() (opens new window) | Easy |
| 29 | Divide Two Integers 两数相除 (opens new window) | Medium |
| 30 | Substring with Concatenation of All Words 串联所有单词的子串 (opens new window) | Hard |
| 31 | Next-permutation 下一个排列 (opens new window) | Medium |
| 32 | Longest Valid Parentheses 最长有效括号 (opens new window) | Hard |
| 33 | Search in Rotated Sorted Array 在旋转有序数组中搜索 (opens new window) | Medium |
| 34 | Search for a Range 搜索范围 (opens new window) | Medium |
| 35 | Search Insert Position 搜索插入位置 (opens new window) | Easy |
| 36 | Valid Sudoku 验证数独 (opens new window) | Medium |
| 37 | Sudoku Solver 解数独 (opens new window) | Hard |
| 38 | Count and Say 数数并说 (opens new window) | Easy |
| 39 | CombinationSum 组合之和 (opens new window) | Medium |
| 40 | CombinationSumII 组合之和 (opens new window) | Medium |
| 41 | First Missing Positive 缺失的第一个正数 (opens new window) | Hard |
| 42 | Trapping Rain Water 接雨水 (opens new window) | Hard |
| 43 | Maximum Subarray 最大子序和 (opens new window) | Medium |
| 44 | Wildcard Matching 通配符匹配 (opens new window) | Hard |
| 45 | Jump Game II 跳跃游戏 II (opens new window) | Hard |
| 46 | Permutations 全排列 (opens new window) | Medium |
| 47 | PermutationsII 全排列 II (opens new window) | Medium |
| 48 | Rotate Image 旋转图像 (opens new window) | Medium |
| 49 | Group Anagrams 字母异位词分组 (opens new window) | Medium |
| 50 | Pow(x, n) Pow(x, n) (opens new window) | Medium |
| 51 | N-Queens N 皇后 (opens new window) | Hard |
| 52 | N-Queens II N 皇后 2 (opens new window) | Hard |
| 53 | Multiply String 字符串相乘 (opens new window) | Medium |
| 54 | Spiral Matrix 螺旋矩阵 (opens new window) | Medium |
| 55 | Jump Game 跳跃游戏 (opens new window) | Medium |
| 56 | Merge Intervals 合并区间 (opens new window) | Medium |
| 57 | Insert Interval 插入区间 (opens new window) | Hard |
| 58 | Length of Last Word 最后一个单词的长度 (opens new window) | Easy |
| 59 | Spiral Matrix II 螺旋矩阵 II (opens new window) | Medium |
| 60 | Permutation Sequence 第 k 个排列 (opens new window) | Medium |
| 61 | Rotate List 旋转链表 (opens new window) | Medium |
| 62 | Unique Paths 不同路径 (opens new window) | Medium |
| 63 | Unique Paths II 不同路径 2 (opens new window) | Medium |
| 64 | Minimum Path Sum 最小路径和 (opens new window) | Medium |
| 65 | Valid Number 有效数字 (opens new window) | Hard |
| 66 | Plus One 加一 (opens new window) | Easy |
| 67 | Add Binary 二进制求和 (opens new window) | Easy |
| 68 | Text Justification 文本左右对齐 (opens new window) | Hard |
| 69 | Sqrt(x) x 的平方根 (opens new window) | Easy |
| 70 | Climbing Stairs 爬楼梯 (opens new window) | Easy |
| 71 | SimplifyPath 简化路径 (opens new window) | Medium |
| 72 | Edit Distance 编辑距离 (opens new window) | Hard |
| 73 | Set Matrix Zeroes 矩阵置零 (opens new window) | Medium |
| 74 | Search a 2D Matrix 搜索二维矩阵 (opens new window) | Medium |
| 75 | Sort Colors 颜色分类 (opens new window) | Medium |
| 77 | Combinations 组合 (opens new window) | Medium |
| 78 | Subsets 子集 (opens new window) | Medium |
| 80 | Remove Duplicates from Sorted Array II 删除排序数组中的重复项 II (opens new window) | Medium |
| 83 | Remove Duplicates from Sorted List 删除排序链表中的重复元素 (opens new window) | Easy |
| 84 | Largest Rectangle in Histogram 柱状图中最大的矩形 (opens new window) | Hard |
| 85 | Maximal Rectangle 最大矩形 (opens new window) | Hard |
| 88 | Merge Sorted Array 合并两个有序数组 (opens new window) | Easy |
| 94 | Binary Tree Inorder Traversal 二叉树的中序遍历 (opens new window) | Medium |
| 100 | Same Tree 相同的树 (opens new window) | Easy |
| 105 | Construct Binary Tree from Preorderand Inorder Traversal 从前序与中序遍历序列构造二叉树 (opens new window) | Medium |
| 107 | Binary Tree Level Order Traversal II 二叉树的层次遍历 II (opens new window) | Easy |
| 109 | Convert Sorted Array to Binary Search Tree 将有序数组转换为二叉搜索树 (opens new window) | Medium |
| 110 | Balanced Binary Tree 平衡二叉树 (opens new window) | Easy |
| 111 | Minimum Depth of Binary Tree 二叉树的最小深度 (opens new window) | Easy |
| 112 | Path Sum 路径总和 (opens new window) | Easy |
| 118 | Pascals Triangle 杨辉三角 (opens new window) | Easy |
| 119 | Pascals Triangle ii 杨辉三角 2 (opens new window) | Easy |
| 125 | IsPalindrome 验证回文串 (opens new window) | Easy |
| 129 | Sum Root to Leaf Numbers 求根到叶子节点数字之和 (opens new window) | Medium |
| 136 | SingleNumber 只出现一次的数字 (opens new window) | Easy |
| 141 | Linked List Cycle 环形链表 (opens new window) | Easy |
| 155 | MinStack 最小栈 (opens new window) | Easy |
| 165 | Compare Version Numbers 比较版本号 (opens new window) | Easy |
| 167 | TwoSum-II 两数之和 II - 输入有序数组 (opens new window) | Easy |
| 169 | MajorityElement 求众数 (opens new window) | Easy |
| 171 | Excel Sheet Column Number Excel 表列序号 (opens new window) | Easy |
| 172 | Factorial Trailing Zeroes 阶乘后的零 (opens new window) | Easy |
| 189 | RotateArray 旋转数组 (opens new window) | Easy |
| 190 | ReverseBits 颠倒二进制位 (opens new window) | Easy |
| 191 | HammingWeight 颠倒二进制位 (opens new window) | Easy |
| 198 | House Robber 打家劫舍 (opens new window) | Easy |
| 199 | Binary Tree Right Side View 二叉树的右视图 (opens new window) | Medium |
| 202 | Happy Number 快乐数 (opens new window) | Easy |
| 203 | Remove Linked List Elements 删除链表中的元素 (opens new window) | Easy |
| 204 | Count Primes 计数质数 (opens new window) | Easy |
| 205 | Isomorphic Strings 同构字符串 (opens new window) | Easy |
| 206 | Reverse Linked List 反转链表 (opens new window) | Easy |
| 217 | ContainsDuplicate 存在重复元素 (opens new window) | Easy |
| 219 | ContainsNearbyDuplicate 存在重复元素 II (opens new window) | Easy |
| 225 | Implement Stack using Queues 用队列实现栈 (opens new window) | Easy |
| 231 | IsPowerOfTwo 2 的幂 (opens new window) | Easy |
| 232 | Implement Queue using Stacks 用栈实现队列 (opens new window) | Easy |
| 238 | Product of Array Except Self 除自身以外数组的乘积 (opens new window) | Medium |
| 242 | Valid Anagram 有效的字母异位词 (opens new window) | Easy |
| 257 | Binary Tree Paths 二叉树的所有路径 (opens new window) | Easy |
| 258 | Add Digits 各位相加 (opens new window) | Easy |
| 263 | Ugly Number 丑数 (opens new window) | Easy |
| 268 | MissingNumber 缺失数字 (opens new window) | Easy |
| 278 | First Bad Version 第一个错误的版本 (opens new window) | Easy |
| 283 | MoveZeroes 移动零 (opens new window) | Easy |
| 287 | Word Pattern 单词规律 (opens new window) | Medium |
| 290 | Word Pattern 单词规律 (opens new window) | Easy |
| 300 | Longest Increasing Subsequence 最长上升子序列 (opens new window) | Medium |
| 303 | Range Sum Query-Immutable 区域和检索 - 数组不可变 (opens new window) | Easy |
| 326 | IsPowerOfThree 3 的幂 (opens new window) | Easy |
| 342 | IsPowerOfFour 4 的幂 (opens new window) | Easy |
| 344 | ReverseString 反转字符串 (opens new window) | Easy |
| 349 | Intersection of Two Arrays 两个数组的交集 (opens new window) | Easy |
| 350 | Intersection of Two ArraysII 两个数组的交集 (opens new window) | Easy |
| 371 | Sum of Two Integers 两个整数相加 (opens new window) | Easy |
| 377 | Combination Sum IV 组合总和 Ⅳ (opens new window) | Medium |
| 383 | Ransom Note 赎金信 (opens new window) | Easy |
| 387 | FirstUniqChar 字符串中的第一个唯一字符 (opens new window) | Easy |
| 389 | FindTheDifference 找不同 (opens new window) | Easy |
| 392 | Is Subsequence 判断子序列 (opens new window) | Easy |
| 400 | Find Nth Digit 第 N 个数字 (opens new window) | Easy |
| 405 | ToHex 转 16 进制 (opens new window) | Easy |
| 414 | ThirdMax 转 16 进制 (opens new window) | Easy |
| 448 | Find All Numbers Disappeared in an Array 找到所有数组中消失的数字 (opens new window) | Easy |
| 455 | Assign Cookies 分发饼干 (opens new window) | Easy |
| 459 | Repeated Substring Pattern 重复的子字符串 (opens new window) | Easy |
| 485 | Find Max Consecutive Ones 最大连续 1 的个数 (opens new window) | Easy |
| 509 | Fibonacci 斐波那契数 (opens new window) | Easy |
| 541 | Reverse String II 反转字符串 II (opens new window) | Easy |
| 561 | ArrayPairSum 数组拆分 I (opens new window) | Easy |
| 581 | Shortest Unsorted Continuous Subarray 最短无序连续子数组 (opens new window) | Easy |
| 606 | Construct String from Binary Tree 根据二叉树创建字符串 (opens new window) | Easy |
| 628 | MaximumProduct 三个数的最大乘积 (opens new window) | Easy |
| 643 | FindMaxAverage 子数组最大平均数 I (opens new window) | Easy |
| 653 | Two Sum IV - Input is a BST 两数之和 IV - 输入 BST (opens new window) | Easy |
| 703 | Kth Largest Element in a Stream 数据流中的第 K 大元素 (opens new window) | Easy |
| 704 | Binary Search 二分查找 (opens new window) | Easy |
| 709 | ToLowerCase 转换成小写字母 (opens new window) | Easy |
| 720 | Longest Word in Dictionary 词典中最长的单词 (opens new window) | Easy |
| 724 | FindPivotIndex 寻找数组的中心索引 (opens new window) | Easy |
| 746 | Min Cost Climbing Stairs 使用最小花费爬楼梯 (opens new window) | Easy |
| 747 | DominantIndex 至少是其他数字两倍的最大数 (opens new window) | Easy |
| 905 | SortArrayByParity 按奇偶排序数组 (opens new window) | Easy |
| 907 | SortedSquares 有序数组的平方 (opens new window) | Easy |
| 933 | Number of Recent Calls 最近的请求次数 (opens new window) | Easy |
| 942 | DI String Match 增减字符串匹配 (opens new window) | Easy |
| 989 | AddToArrayForm 数组形式的整数加法 (opens new window) | Easy |
| 994 | Rotting Oranges 腐烂的橘子 (opens new window) | Easy |
| 1002 | CommonChars 查找常用字符 (opens new window) | Easy |
| 1122 | Relative Sort Array 数组的相对排序 (opens new window) | Easy |
| 1137 | N-th Tribonacci Number 第 N 个泰波那契数 (opens new window) | Easy |
| 1365 | How Many Numbers Are Smaller Than the Current Number 有多少小于当前数字的数字 (opens new window) | Easy |
| 1431 | Kids With the Greatest Number of Candies 拥有最多糖果的孩子 (opens new window) | Easy |
| 1945 | Sum of Digits of String After Convert 字符串转化后的各位数字之和 (opens new window) | Easy |
| 2038 | Remove Colored Pieces if Both Neighbors are the Same Color 如果相邻两个颜色均相同则删除当前颜色 (opens new window) | Easy |