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逆序Serial	题目Title	难度Difficulty
1024	视频拼接 - Video Stitching	Medium
1023	驼峰式匹配 - Camelcase Matching	Medium
1022	从根到叶的二进制数之和 - Sum of Root To Leaf Binary Numbers	Easy
1021	删除最外层的括号 - Remove Outermost Parentheses	Easy
1020	飞地的数量 - Number of Enclaves	Medium
1019	链表中的下一个更大节点 - Next Greater Node In Linked List	Medium
1018	可被 5 整除的二进制前缀 - Binary Prefix Divisible By 5	Easy
1017	负二进制转换 - Convert to Base -2	Medium
1016	子串能表示从 1 到 N 数字的二进制串 - Binary String With Substrings Representing 1 To N	Medium
1015	可被 K 整除的最小整数 - Smallest Integer Divisible by K	Medium
1014	最佳观光组合 - Best Sightseeing Pair	Medium
1013	将数组分成和相等的三个部分 - Partition Array Into Three Parts With Equal Sum	Easy
1012	至少有 1 位重复的数字 - Numbers With 1 Repeated Digit	Hard
1011	在 D 天内送达包裹的能力 - Capacity To Ship Packages Within D Days	Medium
1010	总持续时间可被 60 整除的歌曲 - Pairs of Songs With Total Durations Divisible by 60	Easy
1009	十进制整数的补码 - Complement of Base 10 Integer	Easy
1008	先序遍历构造二叉树 - Construct Binary Search Tree from Preorder Traversal	Medium
1007	行相等的最少多米诺旋转 - Minimum Domino Rotations For Equal Row	Medium
1006	笨阶乘 - Clumsy Factorial	Medium
1005	K 次取反后最大化的数组和 - Maximize Sum Of Array After K Negations	Easy
1004	最大连续1的个数 III - Max Consecutive Ones III	Medium
1003	检查替换后的词是否有效 - Check If Word Is Valid After Substitutions	Medium
1002	查找常用字符 - Find Common Characters	Easy
1001	网格照明 - Grid Illumination	Hard
1000	合并石头的最低成本 - Minimum Cost to Merge Stones	Hard
999	车的可用捕获量 - Available Captures for Rook	Easy
998	最大二叉树 II - Maximum Binary Tree II	Medium
997	找到小镇的法官 - Find the Town Judge	Easy
996	正方形数组的数目 - Number of Squareful Arrays	Hard
995	K 连续位的最小翻转次数 - Minimum Number of K Consecutive Bit Flips	Hard
994	腐烂的橘子 - Rotting Oranges	Easy
993	二叉树的堂兄弟节点 - Cousins in Binary Tree	Easy
992	K 个不同整数的子数组 - Subarrays with K Different Integers	Hard
991	坏了的计算器 - Broken Calculator	Medium
990	等式方程的可满足性 - Satisfiability of Equality Equations	Medium
989	数组形式的整数加法 - Add to Array-Form of Integer	Easy
988	从叶结点开始的最小字符串 - Smallest String Starting From Leaf	Medium
987	二叉树的垂序遍历 - Vertical Order Traversal of a Binary Tree	Medium
986	区间列表的交集 - Interval List Intersections	Medium
985	查询后的偶数和 - Sum of Even Numbers After Queries	Easy
984	不含 AAA 或 BBB 的字符串 - String Without AAA or BBB	Medium
983	最低票价 - Minimum Cost For Tickets	Medium
982	按位与为零的三元组 - Triples with Bitwise AND Equal To Zero	Hard
981	基于时间的键值存储 - Time Based Key-Value Store	Medium
980	不同路径 III - Unique Paths III	Hard
979	在二叉树中分配硬币 - Distribute Coins in Binary Tree	Medium
978	最长湍流子数组 - Longest Turbulent Subarray	Medium
977	有序数组的平方 - Squares of a Sorted Array	Easy
976	三角形的最大周长 - Largest Perimeter Triangle	Easy
975	奇偶跳 - Odd Even Jump	Hard
974	和可被 K 整除的子数组 - Subarray Sums Divisible by K	Medium
973	最接近原点的 K 个点 - K Closest Points to Origin	Medium
972	相等的有理数 - Equal Rational Numbers	Hard
971	翻转二叉树以匹配先序遍历 - Flip Binary Tree To Match Preorder Traversal	Medium
970	强整数 - Powerful Integers	Easy
969	煎饼排序 - Pancake Sorting	Medium
968	监控二叉树 - Binary Tree Cameras	Hard
967	连续差相同的数字 - Numbers With Same Consecutive Differences	Medium
966	元音拼写检查器 - Vowel Spellchecker	Medium
965	单值二叉树 - Univalued Binary Tree	Easy
964	表示数字的最少运算符 - Least Operators to Express Number	Hard
963	最小面积矩形 II - Minimum Area Rectangle II	Medium
962	最大宽度坡 - Maximum Width Ramp	Medium
961	重复 N 次的元素 - N-Repeated Element in Size 2N Array	Easy
960	删列造序 --- - Delete Columns to Make Sorted III	Hard
959	由斜杠划分区域 - Regions Cut By Slashes	Medium
958	二叉树的完全性检验 - Check Completeness of a Binary Tree	Medium
957	N天后的牢房 - Prison Cells After N Days	Medium
956	最高的广告牌 - Tallest Billboard	Hard
955	删列造序 -- - Delete Columns to Make Sorted II	Medium
954	二倍数对数组 - Array of Doubled Pairs	Medium
953	验证外星语词典 - Verifying an Alien Dictionary	Easy
952	按公因数计算最大组件大小 - Largest Component Size by Common Factor	Hard
951	翻转等价二叉树 - Flip Equivalent Binary Trees	Medium
950	按递增顺序显示卡牌 - Reveal Cards In Increasing Order	Medium
949	给定数字能组成的最大时间 - Largest Time for Given Digits	Easy
948	令牌放置 - Bag of Tokens	Medium
947	移除最多的同行或同列石头 - Most Stones Removed with Same Row or Column	Medium
946	验证栈序列 - Validate Stack Sequences	Medium
945	使数组唯一的最小增量 - Minimum Increment to Make Array Unique	Medium
944	删除列以使之有序 - Delete Columns to Make Sorted	Easy
943	最短超级串 - Find the Shortest Superstring	Hard
942	增减字符串匹配 - DI String Match	Easy
941	有效的山脉数组 - Valid Mountain Array	Easy
940	不同的子序列 II - Distinct Subsequences II	Hard
939	最小面积矩形 - Minimum Area Rectangle	Medium
938	二叉搜索树的范围和 - Range Sum of BST	Medium
937	重新排列日志文件 - Reorder Log Files	Easy
936	戳印序列 - Stamping The Sequence	Hard
935	骑士拨号器 - Knight Dialer	Medium
934	最短的桥 - Shortest Bridge	Medium
933	最近的请求次数 - Number of Recent Calls	Easy
932	漂亮数组 - Beautiful Array	Medium
931	下降路径最小和 - Minimum Falling Path Sum	Medium
930	和相同的二元子数组 - Binary Subarrays With Sum	Medium
929	独特的电子邮件地址 - Unique Email Addresses	Easy
928	尽量减少恶意软件的传播 II - Minimize Malware Spread II	Hard
927	三等分 - Three Equal Parts	Hard
926	将字符串翻转到单调递增 - Flip String to Monotone Increasing	Medium
925	长按键入 - Long Pressed Name	Easy
924	尽量减少恶意软件的传播 - Minimize Malware Spread	Hard
923	三数之和的多种可能 - 3Sum With Multiplicity	Medium
922	按奇偶排序数组 II - Sort Array By Parity II	Easy
921	使括号有效的最少添加 - Minimum Add to Make Parentheses Valid	Medium
920	播放列表的数量 - Number of Music Playlists	Hard
919	完全二叉树插入器 - Complete Binary Tree Inserter	Medium
918	环形子数组的最大和 - Maximum Sum Circular Subarray	Medium
917	仅仅反转字母 - Reverse Only Letters	Easy
916	单词子集 - Word Subsets	Medium
915	将分区数组分成不相交的间隔 - Partition Array into Disjoint Intervals	Medium
914	一副牌中的X - X of a Kind in a Deck of Cards	Easy
913	猫与老鼠 - Cat and Mouse	Hard
912
911	在线选举 - Online Election	Medium
910	最小差值 II - Smallest Range II	Medium
909	蛇梯棋 - Snakes and Ladders	Medium
908	最小差值 I - Smallest Range I	Easy
907	子数组的最小值之和 - Sum of Subarray Minimums	Medium
906	超级回文数 - Super Palindromes	Hard
905	按奇偶排序数组 - Sort Array By Parity	Easy
904	水果成篮 - Fruit Into Baskets	Medium
903	DI 序列的有效排列 - Valid Permutations for DI Sequence	Hard
902	最大为 N 的数字组合 - Numbers At Most N Given Digit Set	Hard
901	股票价格跨度 - Online Stock Span	Medium
900	RLE 迭代器 - RLE Iterator	Medium
899	有序队列 - Orderly Queue	Hard
898	子数组按位或操作 - Bitwise ORs of Subarrays	Medium
897	递增顺序查找树 - Increasing Order Search Tree	Easy
896	单调数列 - Monotonic Array	Easy
895	最大频率栈 - Maximum Frequency Stack	Hard
894	所有可能的满二叉树 - All Possible Full Binary Trees	Medium
893	特殊等价字符串组 - Groups of Special-Equivalent Strings	Easy
892	三维形体的表面积 - Surface Area of 3D Shapes	Easy
891	子序列宽度之和 - Sum of Subsequence Widths	Hard
890	查找和替换模式 - Find and Replace Pattern	Medium
889	根据前序和后序遍历构造二叉树 - Construct Binary Tree from Preorder and Postorder Traversal	Medium
888	公平的糖果交换 - Fair Candy Swap	Easy
887	鸡蛋掉落 - Super Egg Drop	Hard
886	可能的二分法 - Possible Bipartition	Medium
885	螺旋矩阵 III - Spiral Matrix III	Medium
884	两句话中的不常见单词 - Uncommon Words from Two Sentences	Easy
883	三维形体投影面积 - Projection Area of 3D Shapes	Easy
882	细分图中的可到达结点 - Reachable Nodes In Subdivided Graph	Hard
881	救生艇 - Boats to Save People	Medium
880	索引处的解码字符串 - Decoded String at Index	Medium
879	盈利计划 - Profitable Schemes	Hard
878	第 N 个神奇数字 - Nth Magical Number	Hard
877	石子游戏 - Stone Game	Medium
876	链表的中间结点 - Middle of the Linked List	Easy
875	爱吃香蕉的珂珂 - Koko Eating Bananas	Medium
874	模拟行走机器人 - Walking Robot Simulation	Easy
873	最长的斐波那契子序列的长度 - Length of Longest Fibonacci Subsequence	Medium
872	叶子相似的树 - Leaf-Similar Trees	Easy
871	最低加油次数 - Minimum Number of Refueling Stops	Hard
870	优势洗牌 - Advantage Shuffle	Medium
869	重新排序得到 2 的幂 - Reordered Power of 2	Medium
868	二进制间距 - Binary Gap	Easy
867	转置矩阵 - Transpose Matrix	Easy
866	回文素数 - Prime Palindrome	Medium
865	具有所有最深结点的最小子树 - Smallest Subtree with all the Deepest Nodes	Medium
864	获取所有钥匙的最短路径 - Shortest Path to Get All Keys	Hard
863	二叉树中所有距离为 K 的结点 - All Nodes Distance K in Binary Tree	Medium
862	和至少为 K 的最短子数组 - Shortest Subarray with Sum at Least K	Hard
861	翻转矩阵后的得分 - Score After Flipping Matrix	Medium
860	柠檬水找零 - Lemonade Change	Easy
859	亲密字符串 - Buddy Strings	Easy
858	镜面反射 - Mirror Reflection	Medium
857	雇佣 K 名工人的最低成本 - Minimum Cost to Hire K Workers	Hard
856	括号的分数 - Score of Parentheses	Medium
855	考场就座 - Exam Room	Medium
854	相似度为 K 的字符串 - K-Similar Strings	Hard
853	车队 - Car Fleet	Medium
852	山脉数组的峰顶索引 - Peak Index in a Mountain Array	Easy
851	喧闹和富有 - Loud and Rich	Medium
850	矩形面积 II - Rectangle Area II	Hard
849	到最近的人的最大距离 - Maximize Distance to Closest Person	Easy
848	字母移位 - Shifting Letters	Medium
847	访问所有节点的最短路径 - Shortest Path Visiting All Nodes	Hard
846	一手顺子 - Hand of Straights	Medium
845	数组中的最长山脉 - Longest Mountain in Array	Medium
844	比较含退格的字符串 - Backspace String Compare	Easy
843	猜猜这个单词 - Guess the Word	Hard
842	将数组拆分成斐波那契序列 - Split Array into Fibonacci Sequence	Medium
841	钥匙和房间 - Keys and Rooms	Medium
840	矩阵中的幻方 - Magic Squares In Grid	Easy
839	相似字符串组 - Similar String Groups	Hard
838	推多米诺 - Push Dominoes	Medium
837	新21点 - New 21 Game	Medium
836	矩形重叠 - Rectangle Overlap	Easy
835	图像重叠 - Image Overlap	Medium
834	树中距离之和 - Sum of Distances in Tree	Hard
833	字符串中的查找与替换 - Find And Replace in String	Medium
832	翻转图像 - Flipping an Image	Easy
831	隐藏个人信息 - Masking Personal Information	Medium
830	较大分组的位置 - Positions of Large Groups	Easy
829	连续整数求和 - Consecutive Numbers Sum	Hard
828	独特字符串 - Unique Letter String	Hard
827	最大人工岛 - Making A Large Island	Hard
826	安排工作以达到最大收益 - Most Profit Assigning Work	Medium
825	适龄的朋友 - Friends Of Appropriate Ages	Medium
824	山羊拉丁文 - Goat Latin	Easy
823	带因子的二叉树 - Binary Trees With Factors	Medium
822	翻转卡片游戏 - Card Flipping Game	Medium
821	字符的最短距离 - Shortest Distance to a Character	Easy
820	单词的压缩编码 - Short Encoding of Words	Medium
819	最常见的单词 - Most Common Word	Easy
818	赛车 - Race Car	Hard
817	链表组件 - Linked List Components	Medium
816	模糊坐标 - Ambiguous Coordinates	Medium
815	公交路线 - Bus Routes	Hard
814	二叉树剪枝 - Binary Tree Pruning	Medium
813	最大平均值和的分组 - Largest Sum of Averages	Medium
812	最大三角形面积 - Largest Triangle Area	Easy
811	子域名访问计数 - Subdomain Visit Count	Easy
810	黑板异或游戏 - Chalkboard XOR Game	Hard
809	情感丰富的文字 - Expressive Words	Medium
808	分汤 - Soup Servings	Medium
807	保持城市天际线 - Max Increase to Keep City Skyline	Medium
806	写字符串需要的行数 - Number of Lines To Write String	Easy
805	数组的均值分割 - Split Array With Same Average	Hard
804	唯一摩尔斯密码词 - Unique Morse Code Words	Easy
803	打砖块 - Bricks Falling When Hit	Hard
802	找到最终的安全状态 - Find Eventual Safe States	Medium
801	使序列递增的最小交换次数 - Minimum Swaps To Make Sequences Increasing	Medium
800		Easy
799	香槟塔 - Champagne Tower	Medium
798	得分最高的最小轮调 - Smallest Rotation with Highest Score	Hard
797	所有可能的路径 - All Paths From Source to Target	Medium
796	旋转字符串 - Rotate String	Easy
795	区间子数组个数 - Number of Subarrays with Bounded Maximum	Medium
794	有效的井字游戏 - Valid Tic-Tac-Toe State	Medium
793	阶乘函数后K个零 - Preimage Size of Factorial Zeroes Function	Hard
792	匹配子序列的单词数 - Number of Matching Subsequences	Medium
791	自定义字符串排序 - Custom Sort String	Medium
790	多米诺和托米诺平铺 - Domino and Tromino Tiling	Medium
789	逃脱阻碍者 - Escape The Ghosts	Medium
788	旋转数字 - Rotated Digits	Easy
787	K 站中转内最便宜的航班 - Cheapest Flights Within K Stops	Medium
786	第 K 个最小的素数分数 - K-th Smallest Prime Fraction	Hard
785	判断二分图 - Is Graph Bipartite?	Medium
784	字母大小写全排列 - Letter Case Permutation	Easy
783	二叉搜索树结点最小距离 - Minimum Distance Between BST Nodes	Easy
782	变为棋盘 - Transform to Chessboard	Hard
781	森林中的兔子 - Rabbits in Forest	Medium
780	到达终点 - Reaching Points	Hard
779	第K个语法符号 - K-th Symbol in Grammar	Medium
778	水位上升的泳池中游泳 - Swim in Rising Water	Hard
777	在LR字符串中交换相邻字符 - Swap Adjacent in LR String	Medium
776		Medium
775	全局倒置与局部倒置 - Global and Local Inversions	Medium
774		Hard
773	滑动谜题 - Sliding Puzzle	Hard
772		Hard
771	宝石与石头 - Jewels and Stones	Easy
770	基本计算器 IV - Basic Calculator IV	Hard
769	最多能完成排序的块 - Max Chunks To Make Sorted	Medium
768	最多能完成排序的块 II - Max Chunks To Make Sorted II	Hard
767	重构字符串 - Reorganize String	Medium
766	托普利茨矩阵 - Toeplitz Matrix	Easy
765	情侣牵手 - Couples Holding Hands	Hard
764	最大加号标志 - Largest Plus Sign	Medium
763	划分字母区间 - Partition Labels	Medium
762	二进制表示中质数个计算置位 - Prime Number of Set Bits in Binary Representation	Easy
761	特殊的二进制序列 - Special Binary String	Hard
760		Easy
759		Hard
758		Easy
757	设置交集大小至少为2 - Set Intersection Size At Least Two	Hard
756	金字塔转换矩阵 - Pyramid Transition Matrix	Medium
755		Medium
754	到达终点数字 - Reach a Number	Easy
753	破解保险箱 - Cracking the Safe	Hard
752	打开转盘锁 - Open the Lock	Medium
751		Easy
750		Medium
749	隔离病毒 - Contain Virus	Hard
748	最短完整词 - Shortest Completing Word	Easy
747	至少是其他数字两倍的最大数 - Largest Number At Least Twice of Others	Easy
746	使用最小花费爬楼梯 - Min Cost Climbing Stairs	Easy
745	前缀和后缀搜索 - Prefix and Suffix Search	Hard
744	寻找比目标字母大的最小字母 - Find Smallest Letter Greater Than Target	Easy
743	网络延迟时间 - Network Delay Time	Medium
742		Medium
741	摘樱桃 - Cherry Pickup	Hard
740	删除与获得点数 - Delete and Earn	Medium
739	每日温度 - Daily Temperatures	Medium
738	单调递增的数字 - Monotone Increasing Digits	Medium
737		Medium
736	Lisp 语法解析 - Parse Lisp Expression	Medium
735	行星碰撞 - Asteroid Collision	Medium
734		Easy
733	图像渲染 - Flood Fill	Easy
732	我的日程安排表 III - My Calendar III	Hard
731	我的日程安排表 II - My Calendar II	Medium
730	统计不同回文子字符串 - Count Different Palindromic Subsequences	Hard
729	我的日程安排表 I - My Calendar I	Medium
728	自除数 - Self Dividing Numbers	Easy
727		Hard
726	原子的数量 - Number of Atoms	Hard
725	分隔链表 - Split Linked List in Parts	Medium
724	寻找数组的中心索引 - Find Pivot Index	Easy
723		Medium
722	删除注释 - Remove Comments	Medium
721	账户合并 - Accounts Merge	Medium
720	词典中最长的单词 - Longest Word in Dictionary	Easy
719	找出第 k 小的距离对 - Find K-th Smallest Pair Distance	Hard
718	最长重复子数组 - Maximum Length of Repeated Subarray	Medium
717	1比特与2比特字符 - 1-bit and 2-bit Characters	Easy
716		Easy
715	Range 模块 - Range Module	Hard
714	买卖股票的最佳时机含手续费 - Best Time to Buy and Sell Stock with Transaction Fee	Medium
713	乘积小于K的子数组 - Subarray Product Less Than K	Medium
712	两个字符串的最小ASCII删除和 - Minimum ASCII Delete Sum for Two Strings	Medium
711		Hard
710	黑名单中的随机数 - Random Pick with Blacklist	Hard
709	转换成小写字母 - To Lower Case	Easy
708		Medium
707	设计链表 - Design Linked List	Easy
706	设计哈希映射 - Design HashMap	Easy
705	设计哈希集合 - Design HashSet	Easy
704	二分查找 - Binary Search	Easy
703	数据流中的第K大元素 - Kth Largest Element in a Stream	Easy
702		Medium
701	二叉搜索树中的插入操作 - Insert into a Binary Search Tree	Medium
700	二叉搜索树中的搜索 - Search in a Binary Search Tree	Easy
699	掉落的方块 - Falling Squares	Hard
698	划分为k个相等的子集 - Partition to K Equal Sum Subsets	Medium
697	数组的度 - Degree of an Array	Easy
696	计数二进制子串 - Count Binary Substrings	Easy
695	岛屿的最大面积 - Max Area of Island	Medium
694		Medium
693	交替位二进制数 - Binary Number with Alternating Bits	Easy
692	前K个高频单词 - Top K Frequent Words	Medium
691	贴纸拼词 - Stickers to Spell Word	Hard
690	员工的重要性 - Employee Importance	Easy
689	三个无重叠子数组的最大和 - Maximum Sum of 3 Non-Overlapping Subarrays	Hard
688	“马”在棋盘上的概率 - Knight Probability in Chessboard	Medium
687	最长同值路径 - Longest Univalue Path	Easy
686	重复叠加字符串匹配 - Repeated String Match	Easy
685	冗余连接 II - Redundant Connection II	Hard
684	冗余连接 - Redundant Connection	Medium
683		Hard
682	棒球比赛 - Baseball Game	Easy
681		Medium
680	验证回文字符串 Ⅱ - Valid Palindrome II	Easy
679	24点游戏 - 24 Game	Medium
678	有效的括号字符串 - Valid Parenthesis String	Medium
677	键值映射 - Map Sum Pairs	Medium
676	实现一个魔法字典 - Implement Magic Dictionary	Medium
675	为高尔夫比赛砍树 - Cut Off Trees for Golf Event	Hard
674	最长连续递增序列 - Longest Continuous Increasing Subsequence	Easy
673	最长递增子序列的个数 - Number of Longest Increasing Subsequence	Medium
672	灯泡开关 Ⅱ - Bulb Switcher II	Medium
671	二叉树中第二小的节点 - Second Minimum Node In a Binary Tree	Easy
670	最大交换 - Maximum Swap	Medium
669	修剪二叉搜索树 - Trim a Binary Search Tree	Easy
668	乘法表中第k小的数 - Kth Smallest Number in Multiplication Table	Hard
667	优美的排列 II - Beautiful Arrangement II	Medium
666		Medium
665	非递减数列 - Non-decreasing Array	Medium
664	奇怪的打印机 - Strange Printer	Medium
663		Medium
662	二叉树最大宽度 - Maximum Width of Binary Tree	Medium
661	图片平滑器 - Image Smoother	Easy
660		Hard
659	分割数组为连续子序列 - Split Array into Consecutive Subsequences	Medium
658	找到 K 个最接近的元素 - Find K Closest Elements	Medium
657	机器人能否返回原点 - Robot Return to Origin	Easy
656		Hard
655	输出二叉树 - Print Binary Tree	Medium
654	最大二叉树 - Maximum Binary Tree	Medium
653	两数之和 IV - 输入 BST - Two Sum IV - Input is a BST	Easy
652	寻找重复的子树 - Find Duplicate Subtrees	Medium
651		Medium
650	只有两个键的键盘 - 2 Keys Keyboard	Medium
649	Dota2 参议院 - Dota2 Senate	Medium
648	单词替换 - Replace Words	Medium
647	回文子串 - Palindromic Substrings	Medium
646	最长数对链 - Maximum Length of Pair Chain	Medium
645	错误的集合 - Set Mismatch	Easy
644		Hard
643	子数组最大平均数 I - Maximum Average Subarray I	Easy
642		Hard
641	设计循环双端队列 - Design Circular Deque	Medium
640	求解方程 - Solve the Equation	Medium
639	解码方法 2 - Decode Ways II	Hard
638	大礼包 - Shopping Offers	Medium
637	二叉树的层平均值 - Average of Levels in Binary Tree	Easy
636	函数的独占时间 - Exclusive Time of Functions	Medium
635		Medium
634		Medium
633	平方数之和 - Sum of Square Numbers	Easy
632	最小区间 - Smallest Range	Hard
631		Hard
630	课程表 III - Course Schedule III	Hard
629	K个逆序对数组 - K Inverse Pairs Array	Hard
628	三个数的最大乘积 - Maximum Product of Three Numbers	Easy
627	交换工资 - Swap Salary	Easy
626	换座位 - Exchange Seats	Medium
625		Medium
624		Easy
623	在二叉树中增加一行 - Add One Row to Tree	Medium
622	设计循环队列 - Design Circular Queue	Medium
621	任务调度器 - Task Scheduler	Medium
620	有趣的电影 - Not Boring Movies	Easy
619		Easy
618		Hard
617	合并二叉树 - Merge Two Binary Trees	Easy
616		Medium
615		Hard
614		Medium
613		Easy
612		Medium
611	有效三角形的个数 - Valid Triangle Number	Medium
610		Easy
609	在系统中查找重复文件 - Find Duplicate File in System	Medium
608		Medium
607		Easy
606	根据二叉树创建字符串 - Construct String from Binary Tree	Easy
605	种花问题 - Can Place Flowers	Easy
604		Easy
603		Easy
602		Medium
601	体育馆的人流量 - Human Traffic of Stadium	Hard
600	不含连续1的非负整数 - Non-negative Integers without Consecutive Ones	Hard
599	两个列表的最小索引总和 - Minimum Index Sum of Two Lists	Easy
598	范围求和 II - Range Addition II	Easy
597		Easy
596	超过5名学生的课 - Classes More Than 5 Students	Easy
595	大的国家 - Big Countries	Easy
594	最长和谐子序列 - Longest Harmonious Subsequence	Easy
593	有效的正方形 - Valid Square	Medium
592	分数加减运算 - Fraction Addition and Subtraction	Medium
591	标签验证器 - Tag Validator	Hard
590		Easy
589		Easy
588		Hard
587	安装栅栏 - Erect the Fence	Hard
586		Easy
585		Medium
584		Easy
583	两个字符串的删除操作 - Delete Operation for Two Strings	Medium
582		Medium
581	最短无序连续子数组 - Shortest Unsorted Continuous Subarray	Easy
580		Medium
579		Hard
578		Medium
577	员工奖金 - Employee Bonus	Easy
576	出界的路径数 - Out of Boundary Paths	Medium
575	分糖果 - Distribute Candies	Easy
574		Medium
573		Medium
572	另一个树的子树 - Subtree of Another Tree	Easy
571		Hard
570		Medium
569		Hard
568		Hard
567	字符串的排列 - Permutation in String	Medium
566	重塑矩阵 - Reshape the Matrix	Easy
565	数组嵌套 - Array Nesting	Medium
564	寻找最近的回文数 - Find the Closest Palindrome	Hard
563	二叉树的坡度 - Binary Tree Tilt	Easy
562		Medium
561	数组拆分 I - Array Partition I	Easy
560	和为K的子数组 - Subarray Sum Equals K	Medium
559		Easy
558		Easy
557	反转字符串中的单词 III - Reverse Words in a String III	Easy
556	下一个更大元素 III - Next Greater Element III	Medium
555		Medium
554	砖墙 - Brick Wall	Medium
553	最优除法 - Optimal Division	Medium
552	学生出勤记录 II - Student Attendance Record II	Hard
551	学生出勤纪录 I - Student Attendance Record I	Easy
550		Medium
549		Medium
548		Medium
547	朋友圈 - Friend Circles	Medium
546	移除盒子 - Remove Boxes	Hard
545		Medium
544		Medium
543	二叉树的直径 - Diameter of Binary Tree	Easy
542	01 矩阵 - 01 Matrix	Medium
541	反转字符串 II - Reverse String II	Easy
540	有序数组中的单一元素 - Single Element in a Sorted Array	Medium
539	最小时间差 - Minimum Time Difference	Medium
538	把二叉搜索树转换为累加树 - Convert BST to Greater Tree	Easy
537	复数乘法 - Complex Number Multiplication	Medium
536		Medium
535		Medium
534		Medium
533		Medium
532	数组中的K-diff数对 - K-diff Pairs in an Array	Easy
531		Medium
530	二叉搜索树的最小绝对差 - Minimum Absolute Difference in BST	Easy
529	扫雷游戏 - Minesweeper	Medium
528	按权重随机选择 - Random Pick with Weight	Medium
527		Hard
526	优美的排列 - Beautiful Arrangement	Medium
525	连续数组 - Contiguous Array	Medium
524	通过删除字母匹配到字典里最长单词 - Longest Word in Dictionary through Deleting	Medium
523	连续的子数组和 - Continuous Subarray Sum	Medium
522	最长特殊序列 II - Longest Uncommon Subsequence II	Medium
521	最长特殊序列 Ⅰ - Longest Uncommon Subsequence I	Easy
520	检测大写字母 - Detect Capital	Easy
519	随机翻转矩阵 - Random Flip Matrix	Medium
518	零钱兑换 II - Coin Change 2	Medium
517	超级洗衣机 - Super Washing Machines	Hard
516	最长回文子序列 - Longest Palindromic	Medium
515	在每个树行中找最大值 - Find Largest Value in Each Tree Row	Medium
514	自由之路 - Freedom Trail	Hard
513	找树左下角的值 - Find Bottom Left Tree Value	Medium
512		Medium
511		Medium
510		Medium
509	斐波那契数 - Fibonacci Number	Easy
508	出现次数最多的子树元素和 - Most Frequent Subtree Sum	Medium
507	完美数 - Perfect Number	Easy
506	相对名次 - Relative Ranks	Easy
505		Medium
504	七进制数 - Base 7	Easy
503	下一个更大元素 II - Next Greater Element II	Medium
502	IPO(首次公开募股) - Initial Public Offerings	Hard
501	二叉搜索树中的众数 - Find Mode in Binary Search Tree	Easy
500	键盘行 - Keyboard Row	Easy
499		Hard
498	对角线遍历 - Diagonal Traverse	Medium
497	非重叠矩形中的随机点 - Random Point in Non-overlapping Rectangles	Medium
496	下一个更大元素 I - Next Greater Element I	Easy
495	提莫攻击 - Teemo Attacking	Medium
494	目标和 - Target Sum	Medium
493	翻转对 - Reverse Pairs	Hard
492	构造矩形 - Construct the Rectangle	Easy
491	递增子序列 - Increasing Subsequences	Medium
490		Medium
489		Hard
488	祖玛游戏 - Zuma Game	Hard
487		Medium
486	预测赢家 - Predict the Winner	Medium
485	最大连续1的个数 - Max Consecutive Ones	Easy
484		Medium
483	最小好进制 - Smallest Good Base	Hard
482	密钥格式化 - License Key Formatting	Easy
481	神奇字符串 - Magical String	Medium
480		Hard
479	最大回文数乘积 - Largest Palindrome Product	Hard
478	在圆内随机生成点 - Generate Random Point in a Circle	Medium
477	汉明距离总和 - Total Hamming Distance	Medium
476	数字的补数 - Number Complement	Easy
475	供暖器 - Heaters	Easy
474	一和零 - Ones and Zeroes	Medium
473	火柴拼正方形 - Matchsticks to Square	Medium
472	连接词 - Concatenated Words	Hard
471		Hard
470	用 Rand7() 实现 Rand10() - Implement Rand10() Using Rand7()	Medium
469		Medium
468	验证IP地址 - Validate IP Address	Medium
467	环绕字符串中唯一的子字符串 - Unique Substrings in Wraparound String	Medium
466	统计重复个数 - Count The Repetitions	Hard
465		Hard
464	我能赢吗 - Can I Win	Medium
463	岛屿的周长 - Island Perimeter	Easy
462	最少移动次数使数组元素相等 II - Minimum Moves to Equal Array Elements II	Medium
461	汉明距离 - Hamming Distance	Easy
460		Hard
459	重复的子字符串 - Repeated Substring Pattern	Easy
458	可怜的小猪 - Poor Pigs	Hard
457	环形数组循环 - Circular Array Loop	Medium
456	132模式 - 132 Pattern	Medium
455	分发饼干 - Assign Cookies	Easy
454	四数相加 II - 4Sum II	Medium
453	最小移动次数使数组元素相等 - Minimum Moves to Equal Array Elements	Easy
452	用最少数量的箭引爆气球 - Minimum Number of Arrows to Burst Balloons	Medium
451	根据字符出现频率排序 - Sort Characters By Frequency	Medium
450	删除二叉搜索树中的节点 - Delete Node in a BST	Medium
449		Medium
448	找到所有数组中消失的数字 - Find All Numbers Disappeared in an Array	Easy
447	回旋镖的数量 - Number of Boomerangs	Easy
446	等差数列划分 II - 子序列 - Arithmetic Slices II - Subsequence	Hard
445	两数相加 II - Add Two Numbers II	Medium
444		Medium
443	压缩字符串 - String Compression	Easy
442	数组中重复的数据 - Find All Duplicates in an Array	Medium
441	排列硬币 - Arranging Coins	Easy
440	字典序的第K小数字 - K-th Smallest in Lexicographical Order	Hard
439		Medium
438	找到字符串中所有字母异位词 - Find All Anagrams in a String	Easy
437	路径总和 III - Path Sum III	Easy
436	寻找右区间 - Find Right Interval	Medium
435	无重叠区间 - Non-overlapping Intervals	Medium
434	字符串中的单词数 - Number of Segments in a String	Easy
433	最小基因变化 - Minimum Genetic Mutation	Medium
432		Hard
431		Hard
430		Medium
429		Easy
428		Hard
427		Easy
426		Medium
425		Hard
424	替换后的最长重复字符 - Longest Repeating Character Replacement	Medium
423	从英文中重建数字 - Reconstruct Original Digits from English	Medium
422		Easy
421	数组中两个数的最大异或值 - Maximum XOR of Two Numbers in an Array	Medium
420	强密码检验器 - Strong Password Checker	Hard
419	甲板上的战舰 - Battleships in a Board	Medium
418		Medium
417	太平洋大西洋水流问题 - Pacific Atlantic Water Flow	Medium
416	分割等和子集 - Partition Equal Subset Sum	Medium
415	字符串相加 - Add Strings	Easy
414	第三大的数 - Third Maximum Number	Easy
413	等差数列划分 - Arithmetic Slices	Medium
412	Fizz Buzz	Easy
411		Hard
410	分割数组的最大值 - Split Array Largest Sum	Hard
409	最长回文串 - Longest Palindrome	Easy
408		Easy
407	接雨水 II - Trapping Rain Water II	Hard
406	根据身高重建队列 - Queue Reconstruction by Height	Medium
405	数字转换为十六进制数 - Convert a Number to Hexadecimal	Easy
404	左叶子之和 - Sum of Left Leaves	Easy
403	青蛙过河 - Frog Jump	Hard
402	移掉K位数字 - Remove K Digits	Medium
401	二进制手表 - Binary Watch	Easy
400	第N个数字 - Nth Digit	Easy
399	除法求值 - Evaluate Division	Medium
398	随机数索引 - Random Pick Index	Medium
397	整数替换 - Integer Replacement	Medium
396	旋转函数 - Rotate Function	Medium
395	至少有K个重复字符的最长子串 - Longest Substring with At Least K Repeating Characters	Medium
394	字符串解码 - Decode String	Medium
393	UTF-8 编码验证 - UTF-8 Validation	Medium
392	判断子序列 - Is Subsequence	Medium
391	完美矩形 - Perfect Rectangle	Hard
390	消除游戏 - Elimination Game	Medium
389	找不同 - Find the Difference	Easy
388	文件的最长绝对路径 - Longest Absolute File Path	Medium
387	字符串中的第一个唯一字符 - First Unique Character in a String	Easy
386	字典序排数 - Lexicographical Numbers	Medium
385	迷你语法分析器 - Mini Parser	Medium
384	打乱数组 - Shuffle an Array	Medium
383	赎金信 - Ransom Note	Easy
382	链表随机节点 - Linked List Random Node	Medium
381	O(1) 时间插入、删除和获取随机元素 - 允许重复 - Insert Delete GetRandom O(1) - Duplicates allowed	Hard
380	常数时间插入、删除和获取随机元素 - Insert Delete GetRandom O(1)	Medium
379		Medium
378	有序矩阵中第K小的元素 - Kth Smallest Element in a Sorted Matrix	Medium
377	组合总和 Ⅳ - Combination Sum IV	Medium
376	摆动序列 - Wiggle Subsequence	Medium
375	猜数字大小 II - Guess Number Higher or Lower II	Medium
374	猜数字大小 - Guess Number Higher or Lower	Easy
373	查找和最小的K对数字 - Find K Pairs with Smallest Sums	Medium
372	超级次方 - Super Pow	Medium
371	两整数之和 - Sum of Two Integers	Easy
370		Medium
369		Medium
368	最大整除子集 - Largest Divisible Subset	Medium
367	有效的完全平方数 - Valid Perfect Square	Easy
366		Medium
365	水壶问题 - Water and Jug Problem	Medium
364		Medium
363	矩形区域不超过 K 的最大数值和 - Max Sum of Rectangle No Larger Than K	Hard
362		Medium
361		Medium
360		Medium
359		Easy
358		Hard
357	计算各个位数不同的数字个数 - Count Numbers with Unique Digits	Medium
356		Medium
355		Medium
354	俄罗斯套娃信封问题 - Russian Doll Envelopes	Hard
353		Medium
352	将数据流变为多个不相交间隔 - Data Stream as Disjoint Intervals	Hard
351		Medium
350	两个数组的交集 II - Intersection of Two Arrays II	Easy
349	两个数组的交集 - Intersection of Two Arrays	Easy
348		Medium
347		Medium
346		Easy
345	反转字符串中的元音字母 - Reverse Vowels of a String	Easy
344	反转字符串 - Reverse String	Easy
343	整数拆分 - Integer Break	Medium
342	4的幂 - Power of Four	Easy
341		Medium
340		Hard
339		Easy
338	比特位计数 - Counting Bits	Medium
337	打家劫舍 III - House Robber III	Medium
336	回文对 - Palindrome Pairs	Hard
335	路径交叉 - Self Crossing	Hard
334	递增的三元子序列 - Increasing Triplet Subsequence	Medium
333		Medium
332	重新安排行程 - Reconstruct Itinerary	Medium
331	验证二叉树的前序序列化 - Verify Preorder Serialization of a Binary Tree	Medium
330		Hard
329	矩阵中的最长递增路径 - Longest Increasing Path in a Matrix	Hard
328	奇偶链表 - Odd Even Linked List	Medium
327	区间和的个数 - Count of Range Sum	Hard
326	3的幂 - Power of Three	Easy
325		Medium
324	摆动排序 II - Wiggle Sort II	Medium
323		Medium
322	零钱兑换 - Coin Change	Medium
321	拼接最大数 - Create Maximum Number	Hard
320		Medium
319	灯泡开关 - Bulb Switcher	Medium
318	最大单词长度乘积 - Maximum Product of Word Lengths	Medium
317		Hard
316	去除重复字母 - Remove Duplicate Letters	Hard
315	计算右侧小于当前元素的个数 - Count of Smaller Numbers After Self	Hard
314		Medium
313	超级丑数 - Super Ugly Number	Medium
312	戳气球 - Burst Balloons	Hard
311		Medium
310	最小高度树 - Minimum Height Trees	Medium
309	最佳买卖股票时机含冷冻期 - Best Time to Buy and Sell Stock with Cooldown	Medium
308		Hard
307	区域和检索 - 数组可修改 - Range Sum Query - Mutable	Medium
306	累加数 - Additive Number	Medium
305		Hard
304	二维区域和检索 - 矩阵不可变 - Range Sum Query 2D - Immutable	Medium
303	区域和检索 - 数组不可变 - Range Sum Query - Immutable	Easy
302		Hard
301	删除无效的括号 - Remove Invalid Parentheses	Hard
300	最长上升子序列 - Longest Increasing Subsequence	Medium
299	猜数字游戏 - Bulls and Cows	Medium
298		Medium
297		Hard
296		Hard
295	数据流的中位数 - Find Median from Data Stream	Hard
294		Medium
293		Easy
292	Nim游戏 - Nim Game	Easy
291		Hard
290	单词模式 - Word Pattern	Easy
289	生命游戏 - Game of Life	Medium
288		Medium
287	寻找重复数 - Find the Duplicate Number	Medium
286		Medium
285		Medium
284		Medium
283	移动零 - Move Zeroes	Easy
282	给表达式添加运算符 - Expression Add Operators	Hard
281		Medium
280		Medium
279	完全平方数 - Perfect Squares	Medium
278	第一个错误的版本 - First Bad Version	Easy
277		Medium
276		Easy
275	H指数 II - H-Index II	Medium
274	H指数 - H-Index	Medium
273	整数转换英文表示 - Integer to English Words	Hard
272		Hard
271	Encode and Decode Strings $ 加码解码字符串	Medium
270	Closest Binary Search Tree Value $ 最近的二分搜索树的值	Easy
269	Alien Dictionary $ 外星人词典	Hard
268	缺失数字 - Missing Number	Easy
267	回文全排列 II $ Palindrome Permutation II	Medium
266	回文全排列 $ Palindrome Permutation	Easy
265	粉刷房子 II $ Paint House II	Hard
264	丑数 II - Ugly Number II	Medium
263	丑数 - Ugly Number	Easy
262	行程和用户 - Trips and Users	Hard
261	图验证树 $ Graph Valid Tree	Medium
260	只出现一次的数字 III - Single Number III	Medium
259	三数之和较小值 $ 3Sum Smaller	Medium
258	各位相加 - Add Digits	Easy
257	二叉树的所有路径 - Binary Tree Paths	Easy
256	粉刷房子 $ Paint House	Easy
255	验证二叉搜索树的先序序列 $ Verify Preorder Sequence in Binary Search Tree	Medium
254	因子组合 $ Factor Combinations	Medium
253	会议室 II $ Meeting Rooms II	Medium
252	会议室 $ Meeting Rooms	Easy
251	展平二维向量 $ Flatten 2D Vector	Medium
250	计数相同值子树的个数 $ Count Univalue Subtrees	Medium
249	群组偏移字符串 $ Group Shifted Strings	Medium
248	对称数 III $ Strobogrammatic Number III	Hard
247	对称数 II $ Strobogrammatic Number II	Medium
246	对称数 $ Strobogrammatic Number	Easy
245	最短单词距离 III $ Shortest Word Distance III	Medium
244	最短单词距离 II $ Shortest Word Distance II	Medium
243	最短单词距离 $ Shortest Word Distance	Easy
242	有效的字母异位词 - Valid Anagram	Easy
241	为运算表达式设计优先级 - Different Ways to Add Parentheses	Medium
240	搜索二维矩阵 II - Search a 2D Matrix II	Medium
239	滑动窗口最大值 - Sliding Window Maximum	Hard
238	除自身以外数组的乘积 - Product of Array Except Self	Medium
237	删除链表中的节点 - Delete Node in a Linked List	Easy
236	二叉树的最近公共祖先 - Lowest Common Ancestor of a Binary Tree	Medium
235	二叉搜索树的最近公共祖先 - Lowest Common Ancestor of a Binary Search Tree	Easy
234	回文链表 - Palindrome Linked List	Easy
233	数字1的个数 - Number of Digit One	Hard
232	用栈实现队列 - Implement Queue using Stacks	Easy
231	2的幂 - Power of Two	Easy
230	二叉搜索树中第K小的元素 - Kth Smallest Element in a BST	Medium
229	求众数 II - Majority Element II	Medium
228	汇总区间 - Summary Ranges	Medium
227	基本计算器 II - Basic Calculator II	Medium
226	翻转二叉树 - Invert Binary Tree	Easy
225	用队列实现栈 - Implement Stack using Queues	Easy
224	基本计算器 - Basic Calculator	Hard
223	矩形面积 - Rectangle Area	Medium
222	完全二叉树的节点个数 - Count Complete Tree Nodes	Medium
221	最大正方形 - Maximal Square	Medium
220	存在重复元素 III - Contains Duplicate III	Medium
219	存在重复元素 II - Contains Duplicate II	Easy
218	天际线问题 - The Skyline Problem	Hard
217	存在重复元素 - Contains Duplicate	Easy
216	组合总和 III - Combination Sum III	Medium
215	数组中的第K个最大元素 - Kth Largest Element in an Array	Medium
214	最短回文串 - Shortest Palindrome	Hard
213	打家劫舍 II - House Robber II	Medium
212	单词搜索 II - Word Search II	Hard
211	添加与搜索单词 - 数据结构设计 - Add and Search Word - Data structure design	Medium
210	课程表 II - Course Schedule II	Medium
209	长度最小的子数组 - Minimum Size Subarray Sum	Medium
208	实现 Trie (前缀树) - Implement Trie (Prefix Tree)	Medium
207	课程表 - Course Schedule	Medium
206	反转链表 - Reverse Linked List	Easy
205	同构字符串 - Isomorphic Strings	Easy
204	计数质数 - Count Primes	Easy
203	移除链表元素 - Remove Linked List Elements	Easy
202	快乐数 - Happy Number	Easy
201	数字范围按位与 - Bitwise AND of Numbers Range	Medium
200	岛屿的个数 - Number of Islands	Medium
199	二叉树的右视图 - Binary Tree Right Side View	Medium
198	打家劫舍 - House Robber	Easy
197	上升的温度 - Rising Temperature	Easy
196	删除重复的电子邮箱 - Delete Duplicate Emails	Easy
195	第十行 - Tenth Line	Easy
194	转置文件 - Transpose File	Medium
193	有效电话号码 - Valid Phone Numbers	Easy
192	统计词频 - Word Frequency	Medium
191	位1的个数 - Number of 1 Bits	Easy
190	颠倒二进制位 - Reverse Bits	Easy
189	旋转数组 - Rotate Array	Easy
188	买卖股票的最佳时机 IV - Best Time to Buy and Sell Stock IV	Hard
187	重复的DNA序列 - Repeated DNA Sequences	Medium
186	翻转字符串中的单词 II $ Reverse Words in a String II	Medium
185	部门工资前三高的员工 - Department Top Three Salaries	Hard
184	部门工资最高的员工 - Department Highest Salary	Medium
183	从不订购的客户 - Customers Who Never Order	Easy
182	查找重复的电子邮箱 - Duplicate Emails	Easy
181	超过经理收入的员工 - Employees Earning More Than Their Managers	Easy
180	连续出现的数字 - Consecutive Numbers	Medium
179	最大数 - Largest Number	Medium
178	分数排名 - Rank Scores	Medium
177	第N高的薪水 - Nth Highest Salary	Medium
176	第二高的薪水 - Second Highest Salary	Easy
175	组合两个表 - Combine Two Tables	Easy
174	地下城游戏 - Dungeon Game	Hard
173	二叉搜索树迭代器 - Binary Search Tree Iterator	Medium
172	阶乘后的零 - Factorial Trailing Zeroes	Easy
171	Excel表列序号 - Excel Sheet Column Number	Easy
170	两数之和之三 - 数据结构设计 $ Two Sum III - Data structure design	Easy
169	求众数 - Majority Element	Easy
168	Excel表列名称 - Excel Sheet Column Title	Easy
167	两数之和 II - 输入有序数组 - Two Sum II - Input array is sorted	Easy
166	分数到小数 - Fraction to Recurring Decimal	Medium
165	比较版本号 - Compare Version Numbers	Medium
164	最大间距 - Maximum Gap	Hard
163	缺失区间 $ Missing Ranges	Medium
162	寻找峰值 - Find Peak Element	Medium
161	一次编辑距离 $ One Edit Distance	Medium
160	相交链表 - Intersection of Two Linked Lists	Easy
159	具有最多两个不同字符的最长子串 $ Longest Substring with At Most Two Distinct Characters	Hard
158	用Read4来读取N个字符II $ Read N Characters Given Read4 II	Hard
157	用Read4来读取N个字符 $ Read N Characters Given Read4	Easy
156	二叉树的上下颠倒 $ Binary Tree Upside Down	Medium
155	最小栈 - Min Stack	Easy
154	寻找旋转排序数组中的最小值 II - Find Minimum in Rotated Sorted Array II	Hard
153	寻找旋转排序数组中的最小值 - Find Minimum in Rotated Sorted Array	Medium
152	乘积最大子序列 - Maximum Product Subarray	Medium
151	翻转字符串里的单词 - Reverse Words in a String	Medium
150	逆波兰表达式求值 - Evaluate Reverse Polish Notation	Medium
149	直线上最多的点数 - Max Points on a Line	Hard
148	排序链表 - Sort List	Medium
147	对链表进行插入排序 - Insertion Sort List	Medium
146	LRU缓存机制 - LRU Cache	Hard
145	二叉树的后序遍历 - Binary Tree Postorder Traversal	Hard
144	二叉树的前序遍历 - Binary Tree Preorder Traversal	Medium
143	重排链表 - Reorder List	Medium
142	环形链表 II - Linked List Cycle II	Medium
141	环形链表 - Linked List Cycle	Easy
140	单词拆分 II - Word Break II	Hard
139	单词拆分 - Word Break	Medium
138	复制带随机指针的链表 - Copy List with Random Pointer	Medium
137	只出现一次的数字 II - Single Number II	Medium
136	只出现一次的数字 - Single Number	Easy
135	分发糖果 - Candy	Hard
134	加油站 - Gas Station	Medium
133	克隆图 - Clone Graph	Medium
132	分割回文串 II - Palindrome Partitioning II	Hard
131	分割回文串 - Palindrome Partitioning	Medium
130	被围绕的区域 - Surrounded Regions	Medium
129	求根到叶子节点数字之和 - Sum Root to Leaf Numbers	Medium
128	最长连续序列 - Longest Consecutive Sequence	Hard
127	单词接龙 - Word Ladder	Medium
126	单词接龙 II - Word Ladder II	Hard
125	验证回文串 - Valid Palindrome	Easy
124	二叉树中的最大路径和 - Binary Tree Maximum Path Sum	Hard
123	买卖股票的最佳时机 III - Best Time to Buy and Sell Stock III	Hard
122	买卖股票的最佳时机 II - Best Time to Buy and Sell Stock II	Easy
121	买卖股票的最佳时机 I - Best Time to Buy and Sell Stock	Easy
120	三角形最小路径和 - Triangle	Medium
119	杨辉三角 II - Pascal's Triangle II	Easy
118	杨辉三角 - Pascal's Triangle	Easy
117	填充同一层的兄弟节点 II - Populating Next Right Pointers in Each Node II	Medium
116	填充同一层的兄弟节点 - Populating Next Right Pointers in Each Node	Medium
115	不同的子序列 - Distinct Subsequences	Hard
114	二叉树展开为链表 - Flatten Binary Tree to Linked List	Medium
113	路径总和 II - Path Sum II	Medium
112	路径总和 - Path Sum	Easy
111	二叉树的最小深度 - Minimum Depth of Binary Tree	Easy
110	平衡二叉树 - Balanced Binary Tree	Easy
109	有序链表转换二叉搜索树 - Convert Sorted List to Binary Search Tree	Medium
108	将有序数组转换为二叉搜索树 - Convert Sorted Array to Binary Search Tree	Easy
107	二叉树的层次遍历 II - Binary Tree Level Order Traversal II	Easy
106	从中序与后序遍历序列构造二叉树 - Construct Binary Tree from Inorder and Postorder Traversal	Medium
105	从前序与中序遍历序列构造二叉树 - Construct Binary Tree from Preorder and Inorder Traversal	Medium
104	二叉树的最大深度 - Maximum Depth of Binary Tree	Easy
103	二叉树的锯齿形层次遍历 - Binary Tree Zigzag Level Order Traversal	Medium
102	二叉树的层次遍历 - Binary Tree Level Order Traversal	Medium
101	对称二叉树 - Symmetric Tree	Easy
100	相同的树 - Same Tree	Hard
99	恢复二叉搜索树 - Recover Binary Search Tree	Medium
98	验证二叉搜索树 - Validate Binary Search Tree	Medium
97	交错字符串 - Interleaving String	Medium
96	不同的二叉搜索树 - Unique Binary Search Trees	Medium
95	不同的二叉搜索树 II - Unique Binary Search Trees II	Medium
94	二叉树的中序遍历 - Binary Tree Inorder Traversal	Medium
93	复原IP地址 - Restore IP Addresses	Medium
92	反转链表 II - Reverse Linked List II	Medium
91	解码方法 - Decode Ways	Medium
90	子集 II - Subsets II	Medium
89	格雷编码 - Gray Code	Medium
88	合并两个有序数组 - Merge Sorted Array	Easy
87	扰乱字符串 - Scramble String	Hard
86	分隔链表 - Partition List	Medium
85	最大矩形 - Maximal Rectangle	Hard
84	柱状图中最大的矩形 - Largest Rectangle in Histogram	Hard
83	删除排序链表中的重复元素 - Remove Duplicates from Sorted List	Easy
82	删除排序链表中的重复元素 II - Remove Duplicates from Sorted List II	Medium
81	搜索旋转排序数组 II - Search in Rotated Sorted Array II	Medium
80	删除排序数组中的重复项 II - Remove Duplicates from Sorted Array II	Medium
79	单词搜索 - Word Search	Medium
78	子集 - Subsets	Medium
77	组合 - Combinations	Medium
76	最小覆盖子串 - Minimum Window Substring	Hard
75	颜色分类 - Sort Colors	Medium
74	搜索二维矩阵 - Search a 2D Matrix	Medium
73	矩阵置零 - Set Matrix Zeroes	Medium
72	编辑距离 - Edit Distance	Hard
71	简化路径 - Simplify Path	Medium
70	爬楼梯 - Climbing Stairs	Easy
69	x 的平方根 - Sqrt(x)	Easy
68	文本左右对齐 - Text Justification	Hard
67	二进制求和 - Add Binary	Easy
66	加一 - Plus One	Easy
65	有效数字 - Valid Number	Hard
64	最小路径和 - Minimum Path Sum	Medium
63	不同路径 II - Unique Paths II	Medium
62	不同路径 - Unique Paths	Medium
61	旋转链表 - Rotate List	Medium
60	第k个排列 - Permutation Sequence	Medium
59	螺旋矩阵 II - Spiral Matrix II	Medium
58	最后一个单词的长度 - Length of Last Word	Easy
57	插入区间 - Insert Interval	Hard
56	合并区间 - Merge Intervals	Medium
55	跳跃游戏 - Jump Game	Medium
54	螺旋矩阵 - Spiral Matrix	Medium
53	最大子序和 - Maximum Subarray	Easy
52	N皇后 II - N-Queens II	Hard
51	N皇后 - N-Queens	Hard
50	Pow(x, n) - Pow(x, n)	Medium
49	字母异位词分组 - Group Anagrams	Medium
48	旋转图像 - Rotate Image	Medium
47	全排列 II - Permutations II	Medium
46	全排列 - Permutations	Medium
45	跳跃游戏 II - Jump Game II	Hard
44	通配符匹配 - Wildcard Matching	Hard
43	字符串相乘 - Multiply Strings	Medium
42	接雨水 - Trapping Rain Water	Hard
41	缺失的第一个正数 - First Missing Positive	Hard
40	组合总和 II - Combination Sum II	Medium
39	组合总和 - Combination Sum	Medium
38	报数 - Count and Say	Easy
37	解数独 - Sudoku Solver	Hard
36	有效的数独 - Valid Sudoku	Medium
35	搜索插入位置 - Search Insert Position	Easy
34	在排序数组中查找元素的第一个和最后一个位置 - Find First and Last Position of Element in Sorted Array	Medium
33	搜索旋转排序数组 - Search in Rotated Sorted Array	Medium
32	最长有效括号 - Longest Valid Parentheses	Hard
31	下一个排列 - Next Permutation	Medium
30	与所有单词相关联的字串 - Substring with Concatenation of All Words	Hard
29	两数相除 - Divide Two Integers	Medium
28	实现strStr() - Implement strStr()	Easy
27	移除元素 - Remove Element	Easy
26	删除排序数组中的重复项 - Remove Duplicates from Sorted Array	Easy
25	k个一组翻转链表 - Reverse Nodes in k-Group	Hard
24	两两交换链表中的节点 - Swap Nodes in Pairs	Medium
23	合并K个排序链表 - Merge k Sorted Lists	Hard
22	括号生成 - Generate Parentheses	Medium
21	合并两个有序链表 - Merge Two Sorted Lists	Easy
20	有效的括号 - Valid Parentheses	Easy
19	删除链表的倒数第N个节点 - Remove Nth Node From End of List	Medium
18	四数之和 - 4Sum	Medium
17	电话号码的字母组合 - Letter Combinations of a Phone Number	Medium
16	最接近的三数之和 - 3Sum Closest	Medium
15	三数之和 - 3Sum	Medium
14	最长公共前缀 - Longest Common Prefix	Easy
13	罗马数字转整数 - Roman to Integer	Easy
12	整数转罗马数字 - Integer to Roman	Medium
11	盛最多水的容器 - Container With Most Water	Medium
10	正则表达式匹配 - Regular Expression Matching	Hard
9	回文数 - Palindrome Number	Easy
8	字符串转整数 (atoi) - String to Integer (atoi)	Medium
7	反转整数 - Reverse Integer	Easy
6	Z字形变换 - ZigZag Conversion	Medium
5	最长回文子串 - Longest Palindromic Substring	Medium
4	两个排序数组的中位数 - Median of Two Sorted Arrays	Hard
3	无重复字符的最长子串 - Longest Substring Without Repeating Characters	Medium
2	两数相加 - Add Two Numbers	Medium
1	两数之和 - Two Sum	Easy