# LeetcodeEveryday
**Repository Path**: Clock966/LeetcodeEveryday
## Basic Information
- **Project Name**: LeetcodeEveryday
- **Description**: 每日 Leetcode
- **Primary Language**: Unknown
- **License**: GPL-2.0
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No
## Statistics
- **Stars**: 1
- **Forks**: 1
- **Created**: 2020-04-11
- **Last Updated**: 2022-05-25
## Categories & Tags
**Categories**: Uncategorized
**Tags**: None
## README
# Leetcode 学习与总结
## 一、电子书(pdf)
Latex排版整理的电子书
- [Backtracking](./ebook/backtracking/leetcode-backtracking.pdf)
- [Graph](./ebook/graph/leetcode-graph.pdf)
- [Tree](./ebook/tree/leetcode-tree.pdf)
- [DP](./ebook/dp/leetcode-dp.pdf)
- [Array](./ebook/array/leetcode-array.pdf)
- [List](./ebook/list/leetcode-list.pdf)
## 二、文档列表
- [刷题要点总结](./doc/Attention.md)
- [Facebook面试总结](./doc/Facebook.md)
- [Bitset技巧](./doc/BitSet.md)
- [Map新接口](./doc/Map.md)
- [其它题目](extras.md)
## 三、所有题目列表
| # | TitleEN | TitleCN | Level | [Java](code_java/README.md) | [C++](code_cpp/README.md) | [Python](code_python\README.md) | Go | Remark |
| ---- | ------------------------------------------------------------ | ---------- | ----- | ------------------------------------------------------------ | ------------------------- | ------------------------------- | ---- | ------------------------------------------------------------ |
| 1 | [Two Sum](https://leetcode-cn.com/problems/two-sum/) | | | [Java解答](code_java/src/solution/TwoSum.java) | | | | |
| 2 | [Add Two Numbers](https://leetcode-cn.com/problems/add-two-numbers/) | | | [Java解答](code_java/src/solution/AddTwoNumber.java) | | | | |
| 3 | [Longest Substring Without Repeating Characters](https://leetcode-cn.com/problems/longest-substring-without-repeating-characters/) | | | [Java解答](code_java/src/solution/LongestSubstringWithoutRepeatingCharacters.java) | | | | 这个系列的所有题都要多做几遍 |
| 4 | [Median of Two Sorted Arrays](https://leetcode-cn.com/problems/median-of-two-sorted-arrays/) | | | [Java解答](code_java/src/solution/MedianOfTwoSortedArrays.java) | | | | 这题很经典，多做几遍 |
| 5 | [Longest Palindromic Substring](https://leetcode-cn.com/problems/longest-palindromic-substring/) | | | [Java解答](code_java/src/solution/LongestPalindromicSubstring.java) | | | | 这题对比动态规划和最优算法 |
| 6 | [ZigZag Conversion](https://leetcode-cn.com/problems/zigzag-conversion/) | | | [Java解答](code_java/src/solution/ZigZagConversion.java) | | | | |
| 7 | [Reverse Integer](https://leetcode-cn.com/problems/reverse-integer/) | | | [Java解答](code_java/src/solution/ReverseInteger.java) | | | | |
| 8 | [String to Integer (atoi)](https://leetcode-cn.com/problems/string-to-integer-atoi/) | | | [Java解答](code_java/src/solution/String2Integer.java) | | | | 很考代码能力，容易错 |
| 9 | [Palindrome Number](https://leetcode-cn.com/problems/palindrome-number/) | | | [Java解答](code_java/src/solution/PalindromeNumber.java) | | | | |
| 10 | [Regular Expression Matching](https://leetcode-cn.com/problems/regular-expression-matching/) | | | [Java解答](code_java/src/solution/RegularExpressionMatching.java) | | | | 这题很经典，多做几遍，和#44一起 |
| 11 | [Container With Most Water](https://leetcode-cn.com/problems/container-with-most-water/) | | | [Java解答](code_java/src/solution/ContainerWithMostWater.java) | | | | |
| 12 | [Integer to Roman](https://leetcode-cn.com/problems/integer-to-roman/) | | | [Java解答](code_java/src/solution/IntegerToRoman.java) | | | | |
| 13 | [Roman to Integer](https://leetcode-cn.com/problems/roman-to-integer/) | | | [Java解答](code_java/src/solution/RomanToInteger.java) | | | | |
| 14 | [Longest Common Prefix](https://leetcode-cn.com/problems/longest-common-prefix/) | | | [Java解答](code_java/src/solution/LongestCommonPrefix.java) | | | | |
| 15 | [3Sum](https://leetcode-cn.com/problems/3sum/) | | | [Java解答](code_java/src/solution/ThreeSum.java) | | | | |
| 16 | [3Sum Closest](https://leetcode-cn.com/problems/3sum-closest/) | | | [Java解答](code_java/src/solution/ThreeSumClosest.java) | | | | |
| 17 | [Letter solution.Combinations of a Phone Number](https://leetcode-cn.com/problems/letter-combinations-of-a-phone-number/) | | | [Java解答](code_java/src/solution/LetterCombinationOfPhoneNumber.java) | | | | |
| 18 | [4Sum](https://leetcode-cn.com/problems/4sum/) | | | [Java解答](code_java/src/solution/FourSum.java) | | | | |
| 19 | [Remove Nth Node From End of List](https://leetcode-cn.com/problems/remove-nth-node-from-end-of-list/) | | | [Java解答](code_java/src/solution/RemoveNthNodeFromEndOfList.java) | | | | |
| 20 | [Valid Parentheses](https://leetcode-cn.com/problems/valid-parentheses/) | | | [Java解答](code_java/src/solution/ValidParentheses.java) | | | | |
| 21 | [Merge Two Sorted Lists](https://leetcode-cn.com/problems/merge-two-sorted-lists/) | | | [Java解答](code_java/src/solution/MergeTwoSortedList.java) | | | | |
| 22 | [Generate Parentheses](https://leetcode-cn.com/problems/generate-parentheses/) | | | [Java解答](code_java/src/solution/GenerateParentheses.java) | | | | 这题看两遍 |
| 23 | [Merge k Sorted Lists](https://leetcode-cn.com/problems/merge-k-sorted-lists/) | | | [Java解答](code_java/src/solution/MergeKSortedList.java) | | | | |
| 24 | [Swap Nodes in Pairs](https://leetcode-cn.com/problems/swap-nodes-in-pairs/) | | | [Java解答](code_java/src/solution/SwapNodesInPairs.java) | | | | |
| 25 | [Reverse Nodes in k-Group](https://leetcode-cn.com/problems/reverse-nodes-in-k-group/) | | | [Java解答](code_java/src/solution/ReverseNodesInKGroup.java) | | | | |
| 26 | [Remove Duplicates from Sorted Array](https://leetcode-cn.com/problems/remove-duplicates-from-sorted-array/) | | | [Java解答](code_java/src/solution/RemoveDuplicatesFromSortedArray.java) | | | | |
| 27 | [Remove Element](https://leetcode-cn.com/problems/remove-element/) | | | [Java解答](code_java/src/solution/RemoveElement.java) | | | | |
| 28 | [ Implement strStr()](https://leetcode-cn.com/problems/implement-strstr/) | | | [Java解答](code_java/src/solution/StrStr.java) | | | | |
| 29 | [Divide Two Integers](https://leetcode-cn.com/problems/divide-two-integers/) | | | [Java解答](code_java/src/solution/DivideTwoIntegers.java) | | | | |
| 30 | [Substring with Concatenation of All Words](https://leetcode-cn.com/problems/substring-with-concatenation-of-all-words/) | | | [Java解答](code_java/src/solution/SubstringWithConcatenationOfAllWords.java) | | | | |
| 31 | [Next Permutation](https://leetcode-cn.com/problems/next-permutation/) | | | [Java解答](code_java/src/solution/NextPermutation.java) | | | | |
| 32 | [Longest Valid Parentheses](https://leetcode-cn.com/problems/longest-valid-parentheses/) | | | [Java解答](code_java/src/solution/LongestValidParentheses.java) | | | | |
| 33 | [Search in Rotated Sorted Array](https://leetcode-cn.com/problems/search-in-rotated-sorted-array/) | | | [Java解答](code_java/src/solution/SearchInRotatedSortedArray.java) | | | | |
| 34 | [Search for a Range](https://leetcode-cn.com/problems/search-for-a-range/) | | | [Java解答](code_java/src/solution/SearchForARange.java) | | | | |
| 35 | [Search Insert Position](https://leetcode-cn.com/problems/search-insert-position/) | | | [Java解答](code_java/src/solution/SearchInsertPosition.java) | | | | |
| 36 | [Valid Sudoku](https://leetcode-cn.com/problems/valid-sudoku/#/description) | | | [Java解答](code_java/src/solution/ValidSudoku.java) | | | | |
| 37 | [Sudoku Solver](https://leetcode-cn.com/problems/sudoku-solver/#/description) | | | [Java解答](code_java/src/solution/SudokuSolver.java) | | | | 这道题是典型的back tracking，多做几遍 |
| 38 | [Count and Say](https://leetcode-cn.com/problems/count-and-say/) | | | [Java解答](code_java/src/solution/CountAndSay.java) | | | | |
| 39 | [Combination Sum](https://leetcode-cn.com/problems/combination-sum/) | | | [Java解答](code_java/src/solution/CombinationSum.java) | | | | 排列组合系列的题要多做几遍 |
| 40 | [Combination Sum II](https://leetcode-cn.com/problems/combination-sum-ii/) | | | [Java解答](code_java/src/solution/CombinationSumII.java) | | | | |
| 41 | [First Missing Positive](https://leetcode-cn.com/problems/first-missing-positive/#/description) | | | [Java解答](code_java/src/solution/FirstMissingPositive.java) | | | | |
| 42 | [Trapping Rain Water](https://leetcode-cn.com/problems/trapping-rain-water/) | | | [Java解答](code_java/src/solution/TrappingRainWater.java) | | | | |
| 43 | [Multiply Strings](https://leetcode-cn.com/problems/multiply-strings/) | | | [Java解答](code_java/src/solution/MultiplyStrings.java) | | | | |
| 44 | [Wildcard Matching](https://leetcode-cn.com/problems/wildcard-matching/) | | | [Java解答](code_java/src/solution/WildcardMatching.java) | | | | 和#10多做几遍 |
| 45 | [Jump Game II](https://leetcode-cn.com/problems/jump-game-ii/#/description) | | | [Java解答](code_java/src/solution/JumpGameII.java) | | | | |
| 46 | [solution.Permutations](https://leetcode-cn.com/problems/permutations/) | | | [Java解答](code_java/src/solution/Permutations.java) | | | | |
| 47 | [solution.Permutations II](https://leetcode-cn.com/problems/permutations-ii/) | | | [Java解答](code_java/src/solution/PermutationsII.java) | | | | 多做几遍 |
| 48 | [Rotate Image](https://leetcode-cn.com/problems/rotate-image/) | | | [Java解答](code_java/src/solution/RotateImage.java) | | | | |
| 49 | [Group Anagrams](https://leetcode-cn.com/problems/anagrams/) | | | [Java解答](code_java/src/solution/GroupAnagrams.java) | | | | |
| 50 | [solution.Pow(x, n)](https://leetcode-cn.com/problems/powx-n/) | | | [Java解答](code_java/src/solution/Pow.java) | | | | |
| 51 | [N-Queens](https://leetcode-cn.com/problems/n-queens/) | | | [Java解答](code_java/src/solution/NQueens.java) | | | | |
| 52 | [N-Queens II](https://leetcode-cn.com/problems/n-queens-ii/) | | | [Java解答](code_java/src/solution/NQueensII.java) | | | | |
| 53 | [Maximum Subarray](https://leetcode-cn.com/problems/maximum-subarray/) | 最大子序和 | easy | [DP算法](code_java/src/solution/MaximumSubarray.java) | | | | DP算法,T=O(N),S=O(1) |
| 54 | [Spiral Matrix](https://leetcode-cn.com/problems/spiral-matrix/) | | | [Java解答](code_java/src/solution/SpiralMatrix.java) | | | | |
| 55 | [Jump Game](https://leetcode-cn.com/problems/jump-game/#/description) | | | [Java解答](code_java/src/solution/JumpGame.java) | | | | |
| 56 | [Merge Intervals](https://leetcode-cn.com/problems/merge-intervals/) | | | [Java解答](code_java/src/solution/MergeIntervals.java) | | | | |
| 57 | [Insert Interval](https://leetcode-cn.com/problems/insert-interval/) | | | [Java解答](code_java/src/solution/InsertInterval.java) | | | | 这题要多做几遍 |
| 60 | [Permutation Sequence](https://leetcode-cn.com/problems/permutation-sequence/) | | | [Java解答](code_java/src/solution/PermutationSequence.java) | | | | 这题思路巧妙，多做两遍 |
| 61 | [Rotate List](https://leetcode-cn.com/problems/rotate-list/) | | | [Java解答](code_java/src/solution/RotateList.java) | | | | |
| 66 | [Plus One](https://leetcode-cn.com/problems/plus-one/) | | | [Java解答](code_java/src/solution/PlusOne.java) | | | | 这题多看一遍 |
| 67 | [Add Binary](https://leetcode-cn.com/problems/add-binary/) | | | [Java解答](code_java/src/solution/AddBinary.java) | | | | |
| 68 | [Text Justification](https://leetcode-cn.com/problems/text-justification/) | | | [Java解答](code_java/src/solution/TextJustification.java) | | | | |
| 69 | [solution.Sqrt(x)](https://leetcode-cn.com/problems/sqrtx/) | | | [Java解答](code_java/src/solution/Sqrt.java) | | | | |
| 70 | [Climb Stairs](https://leetcode-cn.com/problems/climbing-stairs/) | 爬楼梯 | easy | [迭代法/动态规划法/递归法](code_java/src/solution/ClimbingStairs.java) | | | | 可使用迭代法/动态规划法/递归法 |
| 71 | [Simplify Path](https://leetcode-cn.com/problems/simplify-path/) | | | [Java解答](code_java/src/solution/SimplifyPath.java) | | | | |
| 72 | [Edit Distance](https://leetcode-cn.com/problems/edit-distance/) | | | [Java解答](code_java/src/solution/EditDistance.java) | | | | |
| 73 | [Set Matrix Zeroes](https://leetcode-cn.com/problems/set-matrix-zeroes/description/) | | | [Java解答](code_java/src/solution/SetMatrixZeroes.java) | | | | |
| 74 | [Search a 2D Matrix](https://leetcode-cn.com/problems/search-a-2d-matrix/) | | | [Java解答](code_java/src/solution/Search2DMatrix.java) | | | | |
| 75 | [Sort Colors](https://leetcode-cn.com/problems/sort-colors/) | | | [Java解答](code_java/src/solution/SortColors.java) | | | | 这题多做几遍，很有意思 |
| 76 | [Minimum Window Substring](https://leetcode-cn.com/problems/minimum-window-substring/) | | | [Java解答](code_java/src/solution/MinimumWindowSubstring.java) | | | | 这题以及类似的题一定要多做几遍，很经典，参见window |
| 77 | [solution.Combinations](https://leetcode-cn.com/problems/combinations) | | | [Java解答](code_java/src/solution/Combinations.java) | | | | |
| 78 | [solution.Subsets](https://leetcode-cn.com/problems/subsets/) | | | [Java解答](code_java/src/solution/Subsets.java) | | | | |
| 79 | [Word Search](https://leetcode-cn.com/problems/word-search/) | | | [Java解答](code_java/src/solution/WordSearch.java) | | | | |
| 80 | [Remove Duplicates from Sorted Array II](https://leetcode-cn.com/problems/remove-duplicates-from-sorted-array-ii/) | | | [Java解答](code_java/src/solution/RemoveDuplicatesFromSortedArrayII.java) | | | | |
| 81 | [Search in Rotated Sorted Array II](https://leetcode-cn.com/problems/search-in-rotated-sorted-array-ii/) | | | [Java解答](code_java/src/solution/SearchInRotatedSortedArrayII.java) | | | | |
| 82 | [Remove Duplicates from Sorted List II](https://leetcode-cn.com/problems/remove-duplicates-from-sorted-list-ii/) | | | [Java解答](code_java/src/solution/RemoveDuplicatesFromSortedListII.java) | | | | |
| 83 | [Remove Duplicates from Sorted List](https://leetcode-cn.com/problems/remove-duplicates-from-sorted-list/) | | | [Java解答](code_java/src/solution/RemoveDuplicatesFromSortedList.java) | | | | |
| 84 | [Largest Rectangle in Histogram](https://leetcode-cn.com/problems/largest-rectangle-in-histogram/) | | | [Java解答](code_java/src/solution/LargestRectangleInHistogram.java) | | | | |
| 85 | [Maximal Rectangle](https://leetcode-cn.com/problems/maximal-rectangle/) | | | [Java解答](code_java/src/solution/MaximalRectangle.java) | | | | |
| 86 | [Partition List](https://leetcode-cn.com/problems/partition-list/) | | | [Java解答](code_java/src/solution/PartitionList.java) | | | | |
| 88 | [Merge Sorted Array](https://leetcode-cn.com/problems/merge-sorted-array/) | | | [Java解答](code_java/src/solution/MergeSortedArray.java) | | | | |
| 90 | [solution.Subsets II](https://leetcode-cn.com/problems/subsets-ii/) | | | [Java解答](code_java/src/solution/SubsetsII.java) | | | | |
| 91 | [Decode Ways](https://leetcode-cn.com/problems/decode-ways/) | | | [Java解答](code_java/src/solution/DecodeWays.java) | | | | 这题多做几遍，包括#639 |
| 92 | [Reverse Linked List II](https://leetcode-cn.com/problems/reverse-linked-list-ii/) | | | [Java解答](code_java/src/solution/ReverseLinkedListII.java) | | | | |
| 93 | [Restore IP Addresses](https://leetcode-cn.com/problems/restore-ip-addresses/) | | | [Java解答](code_java/src/solution/RestoreIPAddresses.java) | | | | 多看两遍 |
| 94 | [Binary Tree Inorder Traversal](https://leetcode-cn.com/problems/binary-tree-inorder-traversal/) | | | [Java解答](code_java/src/solution/BinaryTreeInorderTraversal.java) | | | | |
| 95 | [Unique Binary Search Trees II](https://leetcode-cn.com/problems/unique-binary-search-trees-ii/) | | | [Java解答](code_java/src/solution/UniqueBinarySearchTreesII.java) | | | | 多做几遍，递归和DP |
| 96 | [Unique Binary Search Trees](https://leetcode-cn.com/problems/unique-binary-search-trees/) | | | [Java解答](code_java/src/solution/UniqueBinarySearchTrees.java) | | | | |
| 98 | [Validate Binary Search Tree](https://leetcode-cn.com/problems/validate-binary-search-tree/) | | | [Java解答](code_java/src/solution/ValidateBinarySearchTree.java) | | | | 注意溢出 |
| 99 | [Recover Binary Search Tree](https://leetcode-cn.com/problems/recover-binary-search-tree/) | | | [Java解答](code_java/src/solution/RecoverBinarySearchTree.java) | | | | 这题很容易错，要多做几遍 |
| 100 | [Same Tree](https://leetcode-cn.com/problems/same-tree/) | | | [Java解答](code_java/src/solution/SameTree.java) | | | | |
| 101 | [Symmetric Tree](https://leetcode-cn.com/problems/symmetric-tree/) | 对称二叉树 | | [Java解答](code_java/src/solution/SymmetricTree.java) | | | | |
| 102 | [Binary Tree Level Order Traversal](https://leetcode-cn.com/problems/binary-tree-level-order-traversal/) | | | [Java解答](code_java/src/solution/BinaryTreeLevelOrderTraversal.java) | | | | |
| 103 | [Binary Tree Zigzag Level Order Traversal](https://leetcode-cn.com/problems/binary-tree-zigzag-level-order-traversal/) | | | [Java解答](code_java/src/solution/BinaryTreeZigzagLevelOrderTraversal.java) | | | | |
| 104 | [Maximum Depth of Binary Tree](https://leetcode-cn.com/problems/maximum-depth-of-binary-tree/) | 最大树深度 | | [Java解答](code_java/src/solution/MaximumDepthOfBinaryTree.java) | | | | |
| 105 | [Construct Binary Tree from Preorder and Inorder Traversal](https://leetcode-cn.com/problems/construct-binary-tree-from-preorder-and-inorder-traversal/) | | | [Java解答](code_java/src/solution/ConstructBinaryTreeFromPreorderInorderTraversal.java) | | | | |
| 106 | [Construct Binary Tree from Inorder and Postorder Traversal](https://leetcode-cn.com/problems/construct-binary-tree-from-inorder-and-postorder-traversal/) | | | [Java解答](code_java/src/solution/ConstructBinaryTreeFromInorderAndPostorderTraversal.java) | | | | |
| 107 | [Binary Tree Level Order Traversal II](https://leetcode-cn.com/problems/binary-tree-level-order-traversal-ii/) | | | [Java解答](code_java/src/solution/BinaryTreeLevelOrderTraversalII.java) | | | | |
| 108 | [Convert Sorted Array to Binary Search Tree](https://leetcode-cn.com/problems/convert-sorted-array-to-binary-search-tree/) | | | [Java解答](code_java/src/solution/ConvertSortedArrayToBinarySearchTree.java) | | | | |
| 109 | [Convert Sorted List to Binary Search Tree](https://leetcode-cn.com/problems/convert-sorted-list-to-binary-search-tree/) | | | [Java解答](code_java/src/solution/ConvertSortedListToBinarySearchTree.java) | | | | |
| 110 | [Balanced Binary Tree](https://leetcode-cn.com/problems/balanced-binary-tree/) | 平衡二叉树 | | [Java解答](code_java/src/solution/BalancedBinaryTree.java) | | | | |
| 111 | [Minimum Depth of Binary Tree](https://leetcode-cn.com/problems/minimum-depth-of-binary-tree/) | | | [Java解答](code_java/src/solution/MinimumDepthOfBinaryTree.java) | | | | |
| 112 | [Path Sum](https://leetcode-cn.com/problems/path-sum/) | | | [Java解答](code_java/src/solution/PathSum.java) | | | | |
| 113 | [Path Sum II](https://leetcode-cn.com/problems/path-sum-ii/) | | | [Java解答](code_java/src/solution/PathSumII.java) | | | | 错了好几次，得多做几遍 |
| 114 | [Flatten Binary Tree to Linked List](https://leetcode-cn.com/problems/flatten-binary-tree-to-linked-list/) | | | [Java解答](code_java/src/solution/FlattenBinaryTreeToLinkedList.java) | | | | |
| 116 | [Populating Next Right Pointers in Each Node](https://leetcode-cn.com/problems/populating-next-right-pointers-in-each-node/) | | | [Java解答](code_java/src/solution/PopulatingNextRightPointersInEachNode.java) | | | | |
| 117 | [Populating Next Right Pointers in Each Node II](https://leetcode-cn.com/problems/populating-next-right-pointers-in-each-node-ii/) | | | [Java解答](code_java/src/solution/PopulatingNextRightPointersInEachNodeII.java) | | | | |
| 118 | [Pascal's Triangle](https://leetcode-cn.com/problems/pascals-triangle/) | | | [Java解答](code_java/src/solution/PascalsTriangle.java) | | | | |
| 119 | [Pascal's Triangle II](https://leetcode-cn.com/problems/pascals-triangle-ii/description/) | | | [Java解答](code_java/src/solution/PascalTriangleII.java) | | | | |
| 121 | [Best Time to Buy and Sell Stock](https://leetcode-cn.com/problems/best-time-to-buy-and-sell-stock/) | | | [Java解答](code_java/src/solution/BestTimeBuySellStock.java) | | | | |
| 122 | [Best Time to Buy and Sell Stock II](https://leetcode-cn.com/problems/best-time-to-buy-and-sell-stock-ii/) | | | [Java解答](code_java/src/solution/BestTimeBuySellStockII.java) | | | | |
| 123 | [Best Time to Buy and Sell Stock III](https://leetcode-cn.com/problems/best-time-to-buy-and-sell-stock-iii/) | | | [Java解答](code_java/src/solution/BestTimeBuySellStockIII.java) | | | | |
| 124 | [Binary Tree Maximum Path Sum](https://leetcode-cn.com/problems/binary-tree-maximum-path-sum/) | | | [Java解答](code_java/src/solution/BinaryTreeMaximumPathSum.java) | | | | |
| 125 | [Valid Palindrome](https://leetcode-cn.com/problems/valid-palindrome/) | | | [Java解答](code_java/src/solution/ValidPalindrome.java) | | | | |
| 126 | [Word Ladder II](https://leetcode-cn.com/problems/word-ladder-ii/) | | | [Java解答](code_java/src/solution/WordLadderII.java) | | | | |
| 127 | [Word Ladder](https://leetcode-cn.com/problems/word-ladder/) | | | [Java解答](code_java/src/solution/WordLadder.java) | | | | 此题非常经典，务必连同ii多做几遍，将双端BFS吃透 |
| 128 | [Longest Consecutive Sequence](https://leetcode-cn.com/problems/longest-consecutive-sequence/) | | | [Java解答](code_java/src/solution/LongestConsecutiveSequence.java) | | | | |
| 129 | [Sum Root to Leaf Numbers](https://leetcode-cn.com/problems/sum-root-to-leaf-numbers/) | | | [Java解答](code_java/src/solution/SumRootToLeafNumbers.java) | | | | |
| 130 | [Surrounded Regions](https://leetcode-cn.com/problems/surrounded-regions/) | | | [Java解答](code_java/src/solution/SurroundedRegions.java) | | | | |
| 131 | [Palindrome Partitioning](https://leetcode-cn.com/problems/palindrome-partitioning/) | | | [Java解答](code_java/src/solution/PalindromePartitioning.java) | | | | |
| 132 | [Palindrome Partitioning II](https://leetcode-cn.com/problems/palindrome-partitioning-ii/) | | | [Java解答](code_java/src/solution/PalindromePartitioningII.java) | | | | |
| 133 | [Clone Graph](https://leetcode-cn.com/problems/clone-graph/) | | | [Java解答](code_java/src/solution/CloneGraph.java) | | | | 这题不难，多看两遍，BFS方法再做两遍 |
| 135 | [solution.Candy](https://leetcode-cn.com/problems/candy/) | | | [Java解答](code_java/src/solution/Candy.java) | | | | |
| 138 | [Copy List with Random Pointer](https://leetcode-cn.com/problems/copy-list-with-random-pointer/) | | | [Java解答](code_java/src/solution/CopyListWithRandomPointer.java) | | | | 有一个易错点 |
| 139 | [Word Break](https://leetcode-cn.com/problems/word-break/) | | | [Java解答](code_java/src/solution/WordBreak.java) | | | | 多看两遍 |
| 140 | [Word Break II](https://leetcode-cn.com/problems/word-break-ii/) | | | [Java解答](code_java/src/solution/WordBreakII.java) | | | | 这题多做两遍，很典型 |
| 141 | [Linked List Cycle](https://leetcode-cn.com/problems/linked-list-cycle/) | | | [Java解答](code_java/src/solution/LinkedListCycle.java) | | | | |
| 142 | [Linked List Cycle II](https://leetcode-cn.com/problems/linked-list-cycle-ii/) | | | [Java解答](code_java/src/solution/LinkedListCycleII.java) | | | | |
| 143 | [Reorder List](https://leetcode-cn.com/problems/reorder-list/) | | | [Java解答](code_java/src/solution/ReorderList.java) | | | | |
| 144 | [Binary Tree Preorder Traversal](https://leetcode-cn.com/problems/binary-tree-preorder-traversal/) | | | [Java解答](code_java/src/solution/BinaryTreePreorderTraversal.java) | | | | |
| 145 | [Binary Tree Postorder Traversal](https://leetcode-cn.com/problems/binary-tree-postorder-traversal/) | | | [Java解答](code_java/src/solution/BinaryTreePostorderTraversal.java) | | | | |
| 146 | [LRU Cache](https://leetcode-cn.com/problems/lru-cache/) | | | [Java解答](code_java/src/solution/LRUCache.java) | | | | 好题目，多做几遍 |
| 147 | [Insertion Sort List](https://leetcode-cn.com/problems/insertion-sort-list/) | | | [Java解答](code_java/src/solution/InsertionSortList.java) | | | | |
| 148 | [Sort List](https://leetcode-cn.com/problems/sort-list) | | | [Java解答](code_java/src/solution/SortList.java) | | | | |
| 149 | [Max Points on a Line](https://leetcode-cn.com/problems/max-points-on-a-line/) | | | [Java解答](code_java/src/solution/MaxPointsOnALine.java) | | | | |
| 150 | [Evaluate Reverse Polish Notation](https://leetcode-cn.com/problems/evaluate-reverse-polish-notation/) | | | [Java解答](code_java/src/solution/EvaluateReversePolishNotation.java) | | | | |
| 151 | [Reverse Words in a String](https://leetcode-cn.com/problems/reverse-words-in-a-string/description/) | | | [Java解答](code_java/src/solution/ReverseWordsInAString.java) | | | | 这题虽然不难，但是也错了几次 |
| 152 | [Maximum Product Subarray](https://leetcode-cn.com/problems/maximum-product-subarray/) | | | [Java解答](code_java/src/solution/MaximumProductSubarray.java) | | | | |
| 153 | [Find Minimum in Rotated Sorted Array](https://leetcode-cn.com/problems/find-minimum-in-rotated-sorted-array/) | | | [Java解答](code_java/src/solution/FindMinimumInRotatedSortedArray.java) | | | | |
| 154 | [Find Minimum in Rotated Sorted Array II](https://leetcode-cn.com/problems/find-minimum-in-rotated-sorted-array-ii/) | | | [Java解答](code_java/src/solution/FindMinimumInRotatedSortedArrayII.java) | | | | |
| 155 | [Min Stack](https://leetcode-cn.com/problems/min-stack/) | | | [Java解答](code_java/src/solution/MinStack.java) | | | | |
| 156 | [Binary Tree Upside Down](https://leetcode-cn.com/problems/binary-tree-upside-down/) | | | [Java解答](code_java/src/solution/BinaryTreeUpsideDown.java) | | | | 这道题挺有意思，多做几遍 |
| 157 | [Read N Characters Given Read4](https://leetcode-cn.com/problems/read-n-characters-given-read4/) | | | [Java解答](code_java/src/solution/ReadNCharactersGivenRead4.java) | | | | 这题多做几遍，结合#158 |
| 158 | [Read N Characters Given Read4 II - Call multiple times](https://leetcode-cn.com/problems/read-n-characters-given-read4-ii-call-multiple-times/) | | | [Java解答](code_java/src/solution/ReadNCharactersGivenRead4II.java) | | | | |
| 159 | [Longest Substring with At Most Two Distinct Characters](https://leetcode-cn.com/problems/longest-substring-with-at-most-two-distinct-characters/) | | | [Java解答](code_java/src/solution/LongestSubstringWithAtMostTwoDistinctCharacters.java) | | | | 多看两遍 |
| 160 | [Intersection of Two Linked Lists](https://leetcode-cn.com/problems/intersection-of-two-linked-lists/) | | | [Java解答](code_java/src/solution/IntersectionOfTwoLinkedLists.java) | | | | |
| 161 | [One Edit Distance](https://leetcode-cn.com/problems/one-edit-distance/) | | | [Java解答](code_java/src/solution/OneEditDistance.java) | | | | 和#72做两遍 |
| 162 | [Find Peak Element](https://leetcode-cn.com/problems/find-peak-element/) | | | [Java解答](code_java/src/solution/FindPeakElement.java) | | | | |
| 163 | [Missing Ranges](https://leetcode-cn.com/problems/missing-ranges/) | | | [Java解答](code_java/src/solution/MissingRanges.java) | | | | 多做几遍，太容易错了 |
| 164 | [Maximum Gap](https://leetcode-cn.com/problems/maximum-gap/) | | | [Java解答](code_java/src/solution/MaximumGap.java) | | | | |
| 167 | [Two Sum II - Input array is sorted](https://leetcode-cn.com/problems/two-sum-ii-input-array-is-sorted/) | | | [Java解答](code_java/src/solution/TwoSumII.java) | | | | |
| 168 | [Excel Sheet Column Title](https://leetcode-cn.com/problems/excel-sheet-column-title/) | | | [Java解答](code_java/src/solution/ExcelSheetColumnTitle.java) | | | | |
| 169 | [Majority Element](https://leetcode-cn.com/problems/majority-element/) | | | [Java解答](code_java/src/solution/MajorityElement.java) | | | | |
| 170 | [Two Sum III - Data structure design](https://leetcode-cn.com/problems/two-sum-iii-data-structure-design/) | | | [Java解答](code_java/src/solution/TwoSumIII.java) | | | | 这道题再多做一遍 |
| 171 | [Excel Sheet Column Number](https://leetcode-cn.com/problems/excel-sheet-column-number/) | | | [Java解答](code_java/src/solution/ExcelSheetColumnNumber.java) | | | | |
| 172 | [Factorial Trailing Zeroes](https://leetcode-cn.com/problems/factorial-trailing-zeroes/) | | | [Java解答](code_java/src/solution/FactorialTrailingZeroes.java) | | | | |
| 173 | [Binary Search Tree Iterator](https://leetcode-cn.com/problems/binary-search-tree-iterator/) | | | [Java解答](code_java/src/solution/BSTIterator.java) | | | | 多留意一下 |
| 179 | [Largest Number](https://leetcode-cn.com/problems/largest-number/) | | | [Java解答](code_java/src/solution/LargestNumber.java) | | | | |
| 186 | [Reverse Words in a String II](https://leetcode-cn.com/problems/reverse-words-in-a-string-ii/description/) | | | [Java解答](code_java/src/solution/ReverseWordsInAStringII.java) | | | | |
| 188 | [Best Time to Buy and Sell Stock IV](https://leetcode-cn.com/problems/best-time-to-buy-and-sell-stock-iv/) | | | [Java解答](code_java/src/solution/BestTimeBuySellStockIV.java) | | | | |
| 189 | [Rotate Array](https://leetcode-cn.com/problems/rotate-array/) | | | [Java解答](code_java/src/solution/RotateArray.java) | | | | |
| 190 | [Reverse Bits](https://leetcode-cn.com/problems/reverse-bits/) | | | [Java解答](code_java/src/solution/ReverseBits.java) | | | | |
| 198 | [House Robber](https://leetcode-cn.com/problems/house-robber/) | | | [Java解答](code_java/src/solution/HouseRobber.java) | | | | |
| 199 | [Binary Tree Right Side View](https://leetcode-cn.com/problems/binary-tree-right-side-view/) | | | [Java解答](code_java/src/solution/BinaryTreeRightSideView.java) | | | | |
| 200 | [Number of Islands](https://leetcode-cn.com/problems/number-of-islands/) | | | [Java解答](code_java/src/solution/NumberOfIslands.java) | | | | 这道题很经典，而且方法不止一种，每种方法都多做几遍，包括UF，#305 |
| 203 | [Remove Linked List Elements](https://leetcode-cn.com/problems/remove-linked-list-elements/) | | | [Java解答](code_java/src/solution/RemoveLinkedListElements.java) | | | | |
| 204 | [Count Primes](https://leetcode-cn.com/problems/count-primes/) | | | [Java解答](code_java/src/solution/CountPrimes.java) | | | | |
| 206 | [Reverse Linked List](https://leetcode-cn.com/problems/reverse-linked-list/) | | | [Java解答](code_java/src/solution/ReverseLinkedList.java) | | | | |
| 207 | [Course Schedule](https://leetcode-cn.com/problems/course-schedule/) | | | [Java解答](code_java/src/solution/CourseSchedule.java) | | | | 典型的拓扑排序 |
| 208 | [Implement solution.Trie (Prefix Tree)](https://leetcode-cn.com/problems/implement-trie-prefix-tree/) | | | [Java解答](code_java/src/solution/Trie.java) | | | | 和#211多留意，trie很典型 |
| 209 | [Minimum Size Subarray Sum](https://leetcode-cn.com/problems/minimum-size-subarray-sum/) | | | [Java解答](code_java/src/solution/MinimumSizeSubarraySum.java) | | | | |
| 210 | [Course Schedule II](https://leetcode-cn.com/problems/course-schedule-ii/) | | | [Java解答](code_java/src/solution/CourseScheduleII.java) | | | | |
| 211 | [Add and Search Word - Data structure design](https://leetcode-cn.com/problems/add-and-search-word-data-structure-design/) | | | [Java解答](code_java/src/solution/WordDictionary.java) | | | | |
| 212 | [Word Search II](https://leetcode-cn.com/problems/word-search-ii/) | | | [Java解答](code_java/src/solution/WordSearchII.java) | | | | |
| 213 | [House Robber II](https://leetcode-cn.com/problems/house-robber-ii/) | | | [Java解答](code_java/src/solution/HouseRobberII.java) | | | | |
| 214 | [Shortest Palindrome](https://leetcode-cn.com/problems/shortest-palindrome/) | | | [Java解答](code_java/src/solution/ShortestPalindrome.java) | | | | |
| 215 | [Kth Largest Element in an Array](https://leetcode-cn.com/problems/kth-largest-element-in-an-array/) | | | [Java解答](code_java/src/solution/KthLargestElementInArray.java) | | | | 这题很经典，三种解法都要了然于胸 |
| 216 | [Combination Sum III](https://leetcode-cn.com/problems/combination-sum-iii/) | | | [Java解答](code_java/src/solution/CombinationSumIII.java) | | | | |
| 217 | [Contains Duplicate](https://leetcode-cn.com/problems/contains-duplicate/) | | | [Java解答](code_java/src/solution/ContainsDuplicate.java) | | | | |
| 218 | [The Skyline Problem](https://leetcode-cn.com/problems/the-skyline-problem/) | | | [Java解答](code_java/src/solution/TheSkylineProblem.java) | | | | 这题多做两遍 |
| 219 | [Contains Duplicate II](https://leetcode-cn.com/problems/contains-duplicate-ii/) | | | [Java解答](code_java/src/solution/ContainsDuplicateII.java) | | | | |
| 220 | [Contains Duplicate III](https://leetcode-cn.com/problems/contains-duplicate-iii/) | | | [Java解答](code_java/src/solution/ContainsDuplicateIII.java) | | | | |
| 221 | [Maximal Square](https://leetcode-cn.com/problems/maximal-square/) | | | [Java解答](code_java/src/solution/MaximalSquare.java) | | | | |
| 222 | [Count Complete Tree Nodes](https://leetcode-cn.com/problems/count-complete-tree-nodes/) | | | [Java解答](code_java/src/solution/CountCompleteTreeNodes.java) | | | | 一般的做法会超时 |
| 223 | [Rectangle Area](https://leetcode-cn.com/problems/rectangle-area/) | | | [Java解答](code_java/src/solution/RectangleArea.java) | | | | |
| 224 | [Basic Calculator](https://leetcode-cn.com/problems/basic-calculator/) | | | [Java解答](code_java/src/solution/BasicCalculator.java) | | | | |
| 225 | [Implement Stack using Queues](https://leetcode-cn.com/problems/implement-stack-using-queues/) | | | [Java解答](code_java/src/solution/MyStack.java) | | | | |
| 226 | [Invert Binary Tree](https://leetcode-cn.com/problems/invert-binary-tree/) | | | [Java解答](code_java/src/solution/InvertBinaryTree.java) | | | | |
| 228 | [Summary Ranges](https://leetcode-cn.com/problems/summary-ranges/) | | | [Java解答](code_java/src/solution/SummaryRanges.java) | | | | |
| 229 | [Majority Element II](https://leetcode-cn.com/problems/majority-element-ii/) | | | [Java解答](code_java/src/solution/MajorityElementII.java) | | | | |
| 230 | [Kth Smallest Element in a BST](https://leetcode-cn.com/problems/kth-smallest-element-in-a-bst/) | | | [Java解答](code_java/src/solution/KthSmallestElementInBST.java) | | | | 注意Follow Up |
| 232 | [Implement Queue using Stacks](https://leetcode-cn.com/problems/implement-queue-using-stacks/) | | | [Java解答](code_java/src/solution/MyQueue.java) | | | | |
| 233 | [Number of Digit One](https://leetcode-cn.com/problems/number-of-digit-one/) | | | [Java解答](code_java/src/solution/NumberOfDigitOne.java) | | | | |
| 234 | [Palindrome Linked List](https://leetcode-cn.com/problems/palindrome-linked-list/) | | | [Java解答](code_java/src/solution/PalindromeLinkedList.java) | | | | |
| 235 | [Lowest Common Ancestor of a Binary Search Tree](https://leetcode-cn.com/problems/lowest-common-ancestor-of-a-binary-search-tree/) | | | [Java解答](code_java/src/solution/LowestCommonAncestorOfBinarySearchTree.java) | | | | |
| 236 | [Lowest Common Ancestor of a Binary Tree](https://leetcode-cn.com/problems/lowest-common-ancestor-of-a-binary-tree/) | | | [Java解答](code_java/src/solution/LowestCommonAncestorOfBinaryTree.java) | | | | 这题很经典，多做几遍，留意节点不在树中的情况 |
| 237 | [Delete Node in a Linked List](https://leetcode-cn.com/problems/delete-node-in-a-linked-list/) | | | [Java解答](code_java/src/solution/DeleteNodeInALinkedList.java) | | | | |
| 238 | [Product of Array Except Self](https://leetcode-cn.com/problems/product-of-array-except-self/) | | | [Java解答](code_java/src/solution/ProductOfArrayExceptSelf.java) | | | | |
| 239 | [Sliding Window Maximum](https://leetcode-cn.com/problems/sliding-window-maximum/) | | | [Java解答](code_java/src/solution/SlidingWindowMaximum.java) | | | | 这题非常经典，多做几遍，包括常规算法(优先队列，treemap)及优化算法双端队列 |
| 240 | [Search a 2D Matrix II](https://leetcode-cn.com/problems/search-a-2d-matrix-ii/) | | | [Java解答](code_java/src/solution/Search2DMatrixII.java) | | | | |
| 241 | [Different Ways to Add Parentheses](https://leetcode-cn.com/problems/different-ways-to-add-parentheses/) | | | [Java解答](code_java/src/solution/DifferenceWaysToAddParentheses.java) | | | | |
| 242 | [Valid Anagram](https://leetcode-cn.com/problems/valid-anagram/) | | | [Java解答](code_java/src/solution/ValidAnagram.java) | | | | |
| 243 | [Shortest Word Distance](https://leetcode-cn.com/problems/shortest-word-distance/) | | | [Java解答](code_java/src/solution/ShortestWordDistance.java) | | | | |
| 244 | [Shortest Word Distance II](https://leetcode-cn.com/problems/shortest-word-distance-ii/) | | | [Java解答](code_java/src/solution/ShortestWordDistanceII.java) | | | | |
| 245 | [Shortest Word Distance III](https://leetcode-cn.com/problems/shortest-word-distance-iii/) | | | [Java解答](code_java/src/solution/ShortestWordDistanceIII.java) | | | | |
| 246 | [Strobogrammatic Number](https://leetcode-cn.com/problems/strobogrammatic-number/) | | | [Java解答](code_java/src/solution/StrobogrammaticNumber.java) | | | | #247一个系列，多看两遍 |
| 247 | [Strobogrammatic Number II](https://leetcode-cn.com/problems/strobogrammatic-number-ii/) | | | [Java解答](code_java/src/solution/src/StrobogrammaticNumberII.java) | | | | 多看两遍 |
| 249 | [Group Shifted Strings](https://leetcode-cn.com/problems/group-shifted-strings/) | | | [Java解答](code_java/src/solution/GroupShiftedStrings.java) | | | | |
| 250 | [Count Univalue Subtrees](https://leetcode-cn.com/problems/count-univalue-subtrees/) | | | [Java解答](code_java/src/solution/CountUnivalueSubtrees.java) | | | | 这题要多做几遍 |
| 251 | [Flatten 2D Vector](https://leetcode-cn.com/problems/flatten-2d-vector/) | | | [Java解答](code_java/src/solution/Vector2D.java) | | | | |
| 252 | [Meeting Rooms](https://leetcode-cn.com/problems/meeting-rooms/) | | | [Java解答](code_java/src/solution/MeetingRooms.java) | | | | |
| 253 | [Meeting Rooms II](https://leetcode-cn.com/problems/meeting-rooms-ii/) | | | [Java解答](code_java/src/solution/MeetingRoomsII.java) | | | | |
| 254 | [Factor solution.Combinations](https://leetcode-cn.com/problems/factor-combinations/) | | | [Java解答](code_java/src/solution/FactorCombinations.java) | | | | |
| 255 | [Verify Preorder Sequence in Binary Search Tree](https://leetcode-cn.com/problems/verify-preorder-sequence-in-binary-search-tree/) | | | [Java解答](code_java/src/solution/VerifyPreorderSequenceInBinarySearchTree.java) | | | | 很简单，粗心错了 |
| 256 | [Paint House](https://leetcode-cn.com/problems/paint-house/) | | | [Java解答](code_java/src/solution/PaintHouse.java) | | | | |
| 257 | [Binary Tree Paths](https://leetcode-cn.com/problems/binary-tree-paths/) | | | [Java解答](code_java/src/solution/BinaryTreePaths.java) | | | | |
| 259 | [3Sum Smaller](https://leetcode-cn.com/problems/3sum-smaller/) | | | [Java解答](code_java/src/solution/ThreeSumSmaller.java) | | | | 这题虽然简单，但是因为思维定式还是错了几次 |
| 261 | [Graph Valid Tree](https://leetcode-cn.com/problems/graph-valid-tree/) | | | [Java解答](code_java/src/solution/GraphValidTree.java) | | | | 这题多做几遍 |
| 263 | [Ugly Number](https://leetcode-cn.com/problems/ugly-number/) | | | [Java解答](code_java/src/solution/UglyNumber.java) | | | | |
| 264 | [Ugly Number II](https://leetcode-cn.com/problems/ugly-number-ii/) | | | [Java解答](code_java/src/solution/UglyNumberII.java) | | | | |
| 265 | [Paint House II](https://leetcode-cn.com/problems/paint-house-ii) | | | [Java解答](code_java/src/solution/PaintHouseII.java) | | | | |
| 266 | [Palindrome Permutation](https://leetcode-cn.com/problems/palindrome-permutation/) | | | [Java解答](code_java/src/solution/PalindromePermutation.java) | | | | |
| 267 | [Palindrome Permutation II](https://leetcode-cn.com/problems/palindrome-permutation-ii/) | | | [Java解答](code_java/src/solution/PalindromePermutationII.java) | | | | 典型，多看两遍 |
| 268 | [Missing Number](https://leetcode-cn.com/problems/missing-number) | | | [Java解答](code_java/src/solution/MissingNumber.java) | | | | |
| 269 | [Alien Dictionary](https://leetcode-cn.com/problems/alien-dictionary/) | | | [Java解答](code_java/src/solution/AlienDictionary.java) | | | | 这题要多做几遍 |
| 270 | [Closest Binary Search Tree Value](https://leetcode-cn.com/problems/closest-binary-search-tree-value/) | | | [Java解答](code_java/src/solution/ClosestBinarySearchTreeValue.java) | | | | |
| 271 | [Encode and Decode Strings](https://leetcode-cn.com/problems/encode-and-decode-strings/) | | | [Java解答](code_java/src/solution/EncodeAndDecodeStrings.java) | | | | 思路巧妙，多看几遍 |
| 272 | [Closest Binary Search Tree Value II](https://leetcode-cn.com/problems/closest-binary-search-tree-value-ii/) | | | [Java解答](code_java/src/solution/ClosestBinarySearchTreeValueII.java) | | | | 这题非常值得多做几遍，几种写法都试试 |
| 273 | [Integer to English Words](https://leetcode-cn.com/problems/integer-to-english-words/) | | | [Java解答](code_java/src/solution/IntegerToEnglishWords.java) | | | | 多做几遍，做到bug free |
| 274 | [H-Index](https://leetcode-cn.com/problems/h-index/) | | | [Java解答](code_java/src/solution/HIndex.java) | | | | |
| 275 | [H-Index II](https://leetcode-cn.com/problems/h-index-ii/) | | | [Java解答](code_java/src/solution/HIndexII.java) | | | | |
| 277 | [Find the Celebrity](https://leetcode-cn.com/problems/find-the-celebrity/) | | | [Java解答](code_java/src/solution/FindCelebrity.java) | | | | |
| 278 | [First Bad Version](https://leetcode-cn.com/problems/first-bad-version/) | | | [Java解答](code_java/src/solution/FirstBadVersion.java) | | | | |
| 279 | [Perfect Squares](https://leetcode-cn.com/problems/perfect-squares/) | | | [Java解答](code_java/src/solution/PerfectSquares.java) | | | | |
| 280 | [Wiggle Sort](https://leetcode-cn.com/problems/wiggle-sort/) | | | [Java解答](code_java/src/solution/WiggleSort.java) | | | | 思路巧妙，多看两遍 |
| 281 | [Zigzag Iterator](https://leetcode-cn.com/problems/zigzag-iterator/) | | | [Java解答](code_java/src/solution/ZigzagIterator.java) | | | | 多做三遍，考虑扩展到k的情况 |
| 282 | [Expression Add Operators](https://leetcode-cn.com/problems/expression-add-operators/) | | | [Java解答](code_java/src/solution/ExpressionAddOperators.java) | | | | |
| 283 | [Move Zeroes](https://leetcode-cn.com/problems/move-zeroes/) | | | [Java解答](code_java/src/solution/MoveZeroes.java) | | | | |
| 284 | [Peeking Iterator](https://leetcode-cn.com/problems/peeking-iterator/) | | | [Java解答](code_java/src/solution/PeekingIterator.java) | | | | |
| 285 | [Inorder Successor in BST](https://leetcode-cn.com/problems/inorder-successor-in-bst/) | | | [Java解答](code_java/src/solution/InorderSuccessorInBST.java) | | | | 这道题有意思，要多做几遍 |
| 286 | [Walls and Gates](https://leetcode-cn.com/problems/walls-and-gates/) | | | [Java解答](code_java/src/solution/WallsAndGates.java) | | | | 多看两遍 |
| 287 | [Find the Duplicate Number](https://leetcode-cn.com/problems/find-the-duplicate-number/) | | | [Java解答](code_java/src/solution/FindTheDuplicateNumber.java) | | | | |
| 288 | [Unique Word Abbreviation](https://leetcode-cn.com/problems/unique-word-abbreviation/) | | | [Java解答](code_java/src/solution/ValidWordAbbr.java) | | | | 这题不难，多做两遍，题目意思容易理解错 |
| 289 | [Game of Life](https://leetcode-cn.com/problems/game-of-life/) | | | [Java解答](code_java/src/solution/GameOfLife.java) | | | | |
| 293 | [Flip Game](https://leetcode-cn.com/problems/flip-game/) | | | [Java解答](code_java/src/solution/FlipGame.java) | | | | |
| 294 | [Flip Game II](https://leetcode-cn.com/problems/flip-game-ii/) | | | [Java解答](code_java/src/solution/FlipGameII.java) | | | | |
| 295 | [Find Median from Data Stream](https://leetcode-cn.com/problems/find-median-from-data-stream/) | | | [Java解答](code_java/src/solution/FindMedianFromDataStream.java) | | | | |
| 297 | [Serialize and Deserialize Binary Tree](https://leetcode-cn.com/problems/serialize-and-deserialize-binary-tree/) | | | [Java解答](code_java/src/solution/Codec.java) | | | | 好题目，多做做，递归的非递归的 |
| 298 | [Binary Tree Longest Consecutive Sequence](https://leetcode-cn.com/problems/binary-tree-longest-consecutive-sequence/) | | | [Java解答](code_java/src/solution/BinaryTreeLongestConsecutiveSequence.java) | | | | 多做三遍，尽可能简洁 |
| 299 | [Bulls and Cows](https://leetcode-cn.com/problems/bulls-and-cows/) | | | [Java解答](code_java/src/solution/BullsAndCows.java) | | | | |
| 300 | [Longest Increasing Subsequence](https://leetcode-cn.com/problems/longest-increasing-subsequence/) | | | [Java解答](code_java/src/solution/LongestIncreasingSubsequence.java) | | | | |
| 301 | [Remove Invalid Parentheses](https://leetcode-cn.com/problems/remove-invalid-parentheses/) | | | [Java解答](code_java/src/solution/RemoveInvalidParentheses.java) | | | | 比较难，多做几遍 |
| 302 | [Smallest Rectangle Enclosing Black Pixels](https://leetcode-cn.com/problems/smallest-rectangle-enclosing-black-pixels/) | | | [Java解答](code_java/src/solution/SmallestRectangleEnclosingBlackPixels.java) | | | | |
| 303 | [Range Sum Query - Immutable](https://leetcode-cn.com/problems/range-sum-query-immutable/) | | | [Java解答](code_java/src/solution/NumArray.java) | | | | |
| 304 | [Range Sum Query 2D - Immutable](https://leetcode-cn.com/problems/range-sum-query-2d-immutable/) | | | [Java解答](code_java/src/solution/NumMatrix.java) | | | | |
| 305 | [Number of Islands II](https://leetcode-cn.com/problems/number-of-islands-ii/) | | | [Java解答](code_java/src/solution/NumberOfIslandsII.java) | | | | 这题多做几遍，经典的UF |
| 307 | [Range Sum Query - Mutable](https://leetcode-cn.com/problems/range-sum-query-mutable/) | | | [Java解答](code_java/src/solution/NumArrayII.java) | | | | 和#303, #304, #308定要多做几遍，掌握BIT |
| 308 | [Range Sum Query 2D - Mutable](https://leetcode-cn.com/problems/range-sum-query-2d-mutable/) | | | [Java解答](code_java/src/solution/NumMatrixII.java) | | | | |
| 309 | [Best Time to Buy and Sell Stock with Cooldown](https://leetcode-cn.com/problems/best-time-to-buy-and-sell-stock-with-cooldown/) | | | [Java解答](code_java/src/solution/BestTimeBuySellStockWithCoolDown.java) | | | | |
| 310 | [Minimum Height Trees](https://leetcode-cn.com/problems/minimum-height-trees/) | | | [Java解答](code_java/src/solution/MinimumHeightTrees.java) | | | | 这题多做几遍 |
| 311 | [Sparse Matrix Multiplication](https://leetcode-cn.com/problems/sparse-matrix-multiplication/) | | | [Java解答](code_java/src/solution/SparseMatrixMultiplication.java) | | | | |
| 312 | [Burst Balloons](https://leetcode-cn.com/problems/burst-balloons/) | | | [Java解答](code_java/src/solution/BurstBalloons.java) | | | | |
| 313 | [Super Ugly Number](https://leetcode-cn.com/problems/super-ugly-number/) | | | [Java解答](code_java/src/solution/SuperUglyNumber.java) | | | | |
| 314 | [Binary Tree Vertical Order Traversal](https://leetcode-cn.com/problems/binary-tree-vertical-order-traversal/) | | | [Java解答](code_java/src/solution/BinaryTreeVerticalOrderTraversal.java) | | | | |
| 315 | [Count of Smaller Numbers After Self](https://leetcode-cn.com/problems/count-of-smaller-numbers-after-self/) | | | [Java解答](code_java/src/solution/CountOfSmallerNumbersAfterSelf.java) | | | | |
| 316 | [Remove Duplicate Letters](https://leetcode-cn.com/problems/remove-duplicate-letters/) | | | [Java解答](code_java/src/solution/RemoveDuplicateLetters.java) | | | | |
| 317 | [Shortest Distance from All Buildings](https://leetcode-cn.com/problems/shortest-distance-from-all-buildings/) | | | [Java解答](code_java/src/solution/ShortestDistanceFromAllBuildings.java) | | | | 典型的bfs，多做两遍 |
| 319 | [Bulb Switcher](https://leetcode-cn.com/problems/bulb-switcher/) | | | [Java解答](code_java/src/solution/BulbSwitcher.java) | | | | |
| 320 | [Generalized Abbreviation](https://leetcode-cn.com/problems/generalized-abbreviation/) | | | [Java解答](code_java/src/solution/GeneralizedAbbreviation.java) | | | | 这题是典型的back tracking，多做几遍 |
| 322 | [Coin Change](https://leetcode-cn.com/problems/coin-change/) | | | [Java解答](code_java/src/solution/CoinChange.java) | | | | |
| 323 | [Number of Connected Components in an Undirected Graph](https://leetcode-cn.com/problems/number-of-connected-components-in-an-undirected-graph/) | | | [Java解答](code_java/src/solution/NumberOfConnectedComponents.java) | | | | 典型的图，多看两遍 |
| 324 | [Wiggle Sort II](https://leetcode-cn.com/problems/wiggle-sort-ii/) | | | [Java解答](code_java/src/solution/WiggleSortII.java) | | | | |
| 325 | [Maximum Size Subarray Sum Equals k](https://leetcode-cn.com/problems/maximum-size-subarray-sum-equals-k/) | | | [Java解答](code_java/src/solution/MaximumSizeSubarraySumEqualsK.java) | | | | 这题思路有意思，多做几遍 |
| 328 | [Odd Even Linked List](https://leetcode-cn.com/problems/odd-even-linked-list/) | | | [Java解答](code_java/src/solution/OddEvenLinkedList.java) | | | | |
| 329 | [Longest Increasing Path in a Matrix](https://leetcode-cn.com/problems/longest-increasing-path-in-a-matrix/) | | | [Java解答](code_java/src/solution/LongestIncreasingPathInAMatrix.java) | | | | 这题要多做几遍 |
| 332 | [Reconstruct Itinerary](https://leetcode-cn.com/problems/reconstruct-itinerary/) | | | [Java解答](code_java/src/solution/ReconstructItinerary.java) | | | | |
| 333 | [Largest BST Subtree](https://leetcode-cn.com/problems/largest-bst-subtree/) | | | [Java解答](code_java/src/solution/LargestBSTSubtree.java) | | | | 这道题虽然不难，但是折腾了很久，一定要多做 |
| 334 | [Increasing Triplet Subsequence](https://leetcode-cn.com/problems/increasing-triplet-subsequence/) | | | [Java解答](code_java/src/solution/IncreasingTripletSubsequence.java) | | | | |
| 335 | [Self Crossing](https://leetcode-cn.com/problems/self-crossing/) | | | [Java解答](code_java/src/solution/SelfCrossing.java) | | | | |
| 336 | [Palindrome Pairs](https://leetcode-cn.com/problems/palindrome-pairs/) | | | [Java解答](code_java/src/solution/PalindromePairs.java) | | | | |
| 337 | [House Robber III](https://leetcode-cn.com/problems/house-robber-iii/) | | | [Java解答](code_java/src/solution/HouseRobberIII.java) | | | | 建议再做两遍 |
| 339 | [Nested List Weight Sum](https://leetcode-cn.com/problems/nested-list-weight-sum/) | | | [Java解答](code_java/src/solution/NestedListWeightSum.java) | | | | |
| 340 | [Longest Substring with At Most K Distinct Characters](https://leetcode-cn.com/problems/longest-substring-with-at-most-k-distinct-characters/) | | | [Java解答](code_java/src/solution/LongestSubstringWithAtMostKDistinctCharacters.java) | | | | 和#159类似 |
| 341 | [Flatten Nested List Iterator](https://leetcode-cn.com/problems/flatten-nested-list-iterator/) | | | [Java解答](code_java/src/solution/src/NestedIterator.java) | | | | 这题有点意思，多做两遍 |
| 344 | [Reverse String](https://leetcode-cn.com/problems/reverse-string/) | | | [Java解答](code_java/src/solution/ReverseString.java) | | | | |
| 345 | [Reverse Vowels of a String](https://leetcode-cn.com/problems/reverse-vowels-of-a-string/) | | | [Java解答](code_java/src/solution/ReverseVowelsOfaString.java) | | | | |
| 346 | [Moving Average from Data Stream](https://leetcode-cn.com/problems/moving-average-from-data-stream/) | | | [Java解答](code_java/src/solution/MovingAverage.java) | | | | |
| 347 | [Top K Frequent Elements](https://leetcode-cn.com/problems/top-k-frequent-elements/) | | | [Java解答](code_java/src/solution/TopKFrequentElements.java) | | | | |
| 349 | [Intersection of Two Arrays](https://leetcode-cn.com/problems/intersection-of-two-arrays/) | | | [Java解答](code_java/src/solution/IntersectionOfTwoArrays.java) | | | | |
| 350 | [Intersection of Two Arrays II](https://leetcode-cn.com/problems/intersection-of-two-arrays-ii/) | | | [Java解答](code_java/src/solution/IntersectionOfTwoArraysII.java) | | | | |
| 351 | [Android Unlock Patterns](https://leetcode-cn.com/problems/android-unlock-patterns/) | | | [Java解答](code_java/src/solution/AndroidUnlockPatterns.java) | | | | 这题多做几遍 |
| 357 | [Count Numbers with Unique Digits](https://leetcode-cn.com/problems/count-numbers-with-unique-digits/) | | | [Java解答](code_java/src/solution/CountNumberWithUniqueDigits.java) | | | | |
| 358 | [Rearrange String k Distance Apart](https://leetcode-cn.com/problems/rearrange-string-k-distance-apart/) | | | [Java解答](code_java/src/solution/RearrangeStringKDistanceApart.java) | | | | |
| 359 | [Logger Rate Limiter](https://leetcode-cn.com/problems/logger-rate-limiter/) | | | [Java解答](code_java/src/solution/LoggerRateLimiter.java) | | | | 这题如果不考虑空间消耗的话其实很简单 |
| 361 | [Bomb Enemy](https://leetcode-cn.com/problems/bomb-enemy/) | | | [Java解答](code_java/src/solution/BombEnemy.java) | | | | 这题多做几遍，开始没思路 |
| 364 | [Nested List Weight Sum II](https://leetcode-cn.com/problems/nested-list-weight-sum-ii/) | | | [Java解答](code_java/src/solution/NestedListWeightSumII.java) | | | | |
| 366 | [Find Leaves of Binary Tree](https://leetcode-cn.com/problems/find-leaves-of-binary-tree/) | | | [Java解答](code_java/src/solution/FindLeavesOfBinaryTree.java) | | | | 这道题刚开始还没思路 |
| 367 | [Valid Perfect Square](https://leetcode-cn.com/problems/valid-perfect-square) | | | [Java解答](code_java/src/solution/ValidPerfectSquare.java) | | | | |
| 369 | [Plus One Linked List](https://leetcode-cn.com/problems/plus-one-linked-list/) | | | [Java解答](code_java/src/solution/PlusOneLinkedList.java) | | | | |
| 370 | [Range Addition](https://leetcode-cn.com/problems/range-addition/) | | | [Java解答](code_java/src/solution/RangeAddition.java) | | | | |
| 373 | [Find K Pairs with Smallest Sums](https://leetcode-cn.com/problems/find-k-pairs-with-smallest-sums/) | | | [Java解答](code_java/src/solution/FindKPairsWithSmallestSums.java) | | | | |
| 374 | [Guess Number Higher or Lower](https://leetcode-cn.com/problems/guess-number-higher-or-lower/) | | | [Java解答](code_java/src/solution/GuessNumberHigherOrLower.java) | | | | |
| 375 | [Guess Number Higher or Lower II](https://leetcode-cn.com/problems/guess-number-higher-or-lower-ii/) | | | [Java解答](code_java/src/solution/GuessNumberHigherOrLowerII.java) | | | | |
| 377 | [Combination Sum IV](https://leetcode-cn.com/problems/combination-sum-iv/) | | | [Java解答](code_java/src/solution/src/combinationSum4.java) | | | | |
| 378 | [Kth Smallest Element in a Sorted Matrix](https://leetcode-cn.com/problems/kth-smallest-element-in-a-sorted-matrix/) | | | [Java解答](code_java/src/solution/KthSmallestElementInASortedMatrix.java) | | | | |
| 380 | [Insert Delete GetRandom O(1)](https://leetcode-cn.com/problems/insert-delete-getrandom-o1/) | | | [Java解答](code_java/src/solution/src/RandomizedSet.java) | | | | 这道题很有意思，多做几遍 |
| 381 | [Insert Delete GetRandom O(1) - Duplicates allowed](https://leetcode-cn.com/problems/insert-delete-getrandom-o1-duplicates-allowed/) | | | [Java解答](code_java/src/solution/src/RandomizedCollection.java) | | | | |
| 382 | [Linked List Random Node](https://leetcode-cn.com/problems/linked-list-random-node/) | | | [Java解答](code_java/src/solution/LinkedListRandomNode.java) | | | | |
| 384 | [Shuffle an Array](https://leetcode-cn.com/problems/shuffle-an-array/) | | | [Java解答](code_java/src/solution/ShuffleAnArray.java) | | | | |
| 387 | [First Unique Character in a String](https://leetcode-cn.com/problems/first-unique-character-in-a-string/) | | | [Java解答](code_java/src/solution/FirstUniqueCharacterInAString.java) | | | | |
| 388 | [Longest Absolute File Path](https://leetcode-cn.com/problems/longest-absolute-file-path/) | | | [Java解答](code_java/src/solution/LongestAbsoluteFilePath.java) | | | | 其实不难，乍看没思路，多做几遍 |
| 391 | [Perfect Rectangle](https://leetcode-cn.com/problems/perfect-rectangle/) | | | [Java解答](code_java/src/solution/PerfectRectangle.java) | | | | 这题很trick，多做两遍 |
| 392 | [Is Subsequence](https://leetcode-cn.com/problems/is-subsequence/)| 判断子序列 | esay | [贪心算法/DP算法](code_java/src/solution/IsSubsequence.java) | | | | DP算法：不建议使用，纯粹学习思想 |
| 393 | [UTF-8 Validation](https://leetcode-cn.com/problems/utf-8-validation/) | | | [Java解答](code_java/src/solution/UTFValidation.java) | | | | 错了很多次，多做几遍 |
| 394 | [Decode String](https://leetcode-cn.com/problems/decode-string/) | | | [Java解答](code_java/src/solution/DecodeString.java) | | | | 这题容易错，多做四遍 |
| 395 | [Longest Substring with At Least K Repeating Characters](https://leetcode-cn.com/problems/longest-substring-with-at-least-k-repeating-characters/) | | | [Java解答](code_java/src/solution/LongestSubstringWithAtLeastKRepeatingCharacters.java) | | | | |
| 398 | [Random Pick Index](https://leetcode-cn.com/problems/random-pick-index/) | | | [Java解答](code_java/src/solution/RandomPickIndex.java) | | | | |
| 399 | [Evaluate Division](https://leetcode-cn.com/problems/evaluate-division/) | | | [Java解答](code_java/src/solution/EvaluateDivision.java) | | | | 这题多做几遍 |
| 401 | [Binary Watch](https://leetcode-cn.com/problems/binary-watch/) | | | [Java解答](code_java/src/solution/BinaryWatch.java) | | | | |
| 404 | [Sum of Left Leaves](https://leetcode-cn.com/problems/sum-of-left-leaves/) | | | [Java解答](code_java/src/solution/SumOfLeftLeaves.java) | | | | |
| 406 | [Queue Reconstruction by Height](https://leetcode-cn.com/problems/queue-reconstruction-by-height/) | | | [Java解答](code_java/src/solution/QueueReconstructionByHeight.java) | | | | 这题开始没思路，多做几遍 |
| 407 | [Trapping Rain Water II](https://leetcode-cn.com/problems/trapping-rain-water-ii/) | | | [Java解答](code_java/src/solution/TrappingRainWaterII.java) | | | | |
| 408 | [Valid Word Abbreviation](https://leetcode-cn.com/problems/valid-word-abbreviation/) | | | [Java解答](code_java/src/solution/src/validWordAbbreviation.java) | | | | 多做两遍 |
| 409 | [Longest Palindrome](https://leetcode-cn.com/problems/longest-palindrome/) | | | [Java解答](code_java/src/solution/LongestPalindrome.java) | | | | |
| 410 | [Split Array Largest Sum](https://leetcode-cn.com/problems/split-array-largest-sum) | | | [Java解答](code_java/src/solution/SplitArrayLargestSum.java) | | | | |
| 412 | [Fizz Buzz](https://leetcode-cn.com/problems/fizz-buzz/) | | | [Java解答](code_java/src/solution/FizzBuzz.java) | | | | |
| 413 | [Third Maximum Number](https://leetcode-cn.com/problems/third-maximum-number/) | | | [Java解答](code_java/src/solution/ThirdMaximumNumber.java) | | | | |
| 418 | [Sentence Screen Fitting](https://leetcode-cn.com/problems/sentence-screen-fitting/) | | | [Java解答](code_java/src/solution/SentenceScreenFitting.java) | | | | 这题思路巧妙，多做几遍，常规思路超时 |
| 422 | [Valid Word Square](https://leetcode-cn.com/problems/valid-word-square/) | | | [Java解答](code_java/src/solution/ValidWordSquare.java) | | | | |
| 425 | [Word Squares](https://leetcode-cn.com/problems/word-squares/) | | | [Java解答](code_java/src/solution/src/WordSquare.java) | | | | 这题很典型，多做几遍 |
| 436 | [Find Right Interval](https://leetcode-cn.com/problems/find-right-interval/) | | | [Java解答](code_java/src/solution/FindRightInterval.java) | | | | |
| 437 | [Path Sum III](https://leetcode-cn.com/problems/path-sum-iii/) | | | [Java解答](code_java/src/solution/PathSumIII.java) | | | | 这道题错了很多遍，要重点关注 |
| 438 | [Find All Anagrams in a String](https://leetcode-cn.com/problems/find-all-anagrams-in-a-string/) | | | [Java解答](code_java/src/solution/FindAllAnagramsInString.java) | | | | 这道题非常经典，最优解法需要多做几遍，保证once bug free |
| 442 | [Find All Duplicates in an Array](https://leetcode-cn.com/problems/find-all-duplicates-in-an-array/) | | | [Java解答](code_java/src/solution/FindAllDuplicatesInAnArray.java) | | | | |
| 445 | [Add Two Numbers II](https://leetcode-cn.com/problems/add-two-numbers-ii/discuss/) | | | [Java解答](code_java/src/solution/AddTwoNumbersII.java) | | | | |
| 448 | [Find All Numbers Disappeared in an Array](https://leetcode-cn.com/problems/find-all-numbers-disappeared-in-an-array) | | | [Java解答](code_java/src/solution/FindAllNumbersDisappearedInAnArray.java) | | | | |
| 449 | [Serialize and Deserialize BST](https://leetcode-cn.com/problems/serialize-and-deserialize-bst) | | | [Java解答](code_java/src/solution/SerializeAndDeserializeBST.java) | | | | 和#297一样 |
| 450 | [Delete Node in a BST](https://leetcode-cn.com/problems/delete-node-in-a-bst/) | | | [Java解答](code_java/src/solution/DeleteNodeInBST.java) | | | | 这题非常经典，值得多做十遍 |
| 451 | [Sort Characters By Frequency](https://leetcode-cn.com/problems/sort-characters-by-frequency/) | | | [Java解答](code_java/src/solution/SortCharactersByFrequency.java) | | | | |
| 455 | [Assign Cookies](https://leetcode-cn.com/problems/assign-cookies/) | 分发饼干 | esay | [贪心算法](code_java/src/solution/AssignCookies.java) | | | | | |
| 459 | [Repeated Substring Pattern](https://leetcode-cn.com/problems/repeated-substring-pattern/) | | | [Java解答](code_java/src/solution/RepeatedSubstringPattern.java) | | | | |
| 477 | [Total Hamming Distance](https://leetcode-cn.com/problems/total-hamming-distance/) | | | [Java解答](code_java/src/solution/TotalHammingDistance.java) | | | | |
| 480 | [Sliding Window Median](https://leetcode-cn.com/problems/sliding-window-median/) | | | [Java解答](code_java/src/solution/SlidingWindowMedian.java) | | | | |
| 482 | [License Key Formatting](https://leetcode-cn.com/problems/license-key-formatting/) | | | [Java解答](code_java/src/solution/LicenseKeyFormatting.java) | | | | |
| 483 | [Smallest Good Base](https://leetcode-cn.com/problems/smallest-good-base/) | | | [Java解答](code_java/src/solution/SmallestGoodBase.java) | | | | |
| 485 | [Max Consecutive Ones](https://leetcode-cn.com/problems/max-consecutive-ones/) | | | [Java解答](code_java/src/solution/MaxConsecutiveOnes.java) | | | | |
| 487 | [Max Consecutive Ones II](https://leetcode-cn.com/problems/max-consecutive-ones-ii/) | | | [Java解答](code_java/src/solution/MaxConsecutiveOnesII.java) | | | | |
| 501 | [Find Mode in Binary Search Tree](https://leetcode-cn.com/problems/find-mode-in-binary-search-tree/) | | | [Java解答](code_java/src/solution/FindModeInBinarySearchTree.java) | | | | 不难，容易错，多做两次 |
| 508 | [Most Frequent Subtree Sum](https://leetcode-cn.com/problems/most-frequent-subtree-sum/submissions/) | | | [Java解答](code_java/src/solution/MostFrequentSubtreeSum.java) | | | | |
| 513 | [Find Bottom Left Tree Value](https://leetcode-cn.com/problems/find-bottom-left-tree-value/) | | | [Java解答](code_java/src/solution/FindBottomLeftTreeValue.java) | | | | |
| 515 | [Find Largest Value in Each Tree Row](https://leetcode-cn.com/problems/find-largest-value-in-each-tree-row/) | | | [Java解答](code_java/src/solution/FindLargestValueInEachTreeRow.java) | | | | |
| 524 | [Longest Word in Dictionary through Deleting](https://leetcode-cn.com/problems/longest-word-in-dictionary-through-deleting/) | | | [Java解答](code_java/src/solution/LongestWordInDictionaryThroughDeleting.java) | | | | |
| 526 | [Beautiful Arrangement](https://leetcode-cn.com/problems/beautiful-arrangement/) | | | [Java解答](code_java/src/solution/BeautifulArrangement.java) | | | | |
| 535 | [Encode and Decode TinyURL](https://leetcode-cn.com/problems/encode-and-decode-tinyurl/) | | | [Java解答](code_java/src/solution/EncodeAndDecodeTinyURL.java) | | | | |
| 538 | [Convert BST to Greater Tree](https://leetcode-cn.com/problems/convert-bst-to-greater-tree/) | | | [Java解答](code_java/src/solution/ConvertBSTToGreaterTree.java) | | | | |
| 541 | [Reverse String II](https://leetcode-cn.com/problems/reverse-string-ii/) | | | [Java解答](code_java/src/solution/ReverseStringII.java) | | | | |
| 543 | [Diameter of Binary Tree](https://leetcode-cn.com/problems/diameter-of-binary-tree/) | | | [Java解答](code_java/src/solution/DiameterOfBinaryTree.java) | | | | 这题易错 |
| 547 | [Friend Circles](https://leetcode-cn.com/problems/friend-circles/) | | | [Java解答](code_java/src/solution/FriendCircles.java) | | | | |
| 557 | [Reverse Words in a String III](https://leetcode-cn.com/problems/reverse-words-in-a-string-iii/) | | | [Java解答](code_java/src/solution/ReverseWordsInAStringIII.java) | | | | |
| 560 | [Subarray Sum Equals K](https://leetcode-cn.com/problems/subarray-sum-equals-k/) | | | [Java解答](code_java/src/solution/SubarraySumEqualsK.java) | | | | |
| 563 | [Binary Tree Tilt](https://leetcode-cn.com/problems/binary-tree-tilt/) | | | [Java解答](code_java/src/solution/BinaryTreeTilt.java) | | | | |
| 564 | [Find the Closest Palindrome](https://leetcode-cn.com/problems/find-the-closest-palindrome/) | | | [Java解答](code_java/src/solution/FindTheClosestPalindrome.java) | | | | 此题暴力法即可 |
| 572 | [Subtree of Another Tree](https://leetcode-cn.com/problems/subtree-of-another-tree/) | | | [Java解答](code_java/src/solution/SubtreeOfAnotherTree.java) | | | | |
| 606 | [Construct String from Binary Tree](https://leetcode-cn.com/problems/construct-string-from-binary-tree/) | | | [Java解答](code_java/src/solution/ConstructStringFromBinaryTree.java) | | | | |
| 617 | [Merge Two Binary Trees](https://leetcode-cn.com/problems/merge-two-binary-trees/) | | | [Java解答](code_java/src/solution/MergeTwoBinaryTrees.java) | | | | 很简单 |
| 621 | [Task Scheduler](https://leetcode-cn.com/problems/task-scheduler/) | | | [Java解答](code_java/src/solution/TaskScheduler.java) | | | | |
| 637 | [Average of Levels in Binary Tree](https://leetcode-cn.com/problems/average-of-levels-in-binary-tree/#/description) | | | [Java解答](code_java/src/solution/AverageOfLevelsInBinaryTree.java) | | | | |
| 652 | [Find Duplicate Subtrees](https://leetcode-cn.com/problems/find-duplicate-subtrees/) | | | [Java解答](code_java/src/solution/FindDuplicateSubtrees.java) | | | | 开始还没思路 |
| 653 | [Two Sum IV - Input is a BST](https://leetcode-cn.com/problems/two-sum-iv-input-is-a-bst/) | | | [Java解答](code_java/src/solution/TwoSumIV.java) | | | | |
| 654 | [Maximum Binary Tree](https://leetcode-cn.com/problems/maximum-binary-tree/description/) | | | [Java解答](code_java/src/solution/MaximumBinaryTree.java) | | | | |
| 669 | [Trim a Binary Search Tree](https://leetcode-cn.com/problems/trim-a-binary-search-tree/) | | | [Java解答](code_java/src/solution/TrimABinarySearchTree.java) | | | | |
| 681 | [Next Closest Time](https://leetcode-cn.com/problems/next-closest-time/) | | | [Java解答](code_java/src/solution/NextClosestTime.java) | | | | 这题多做几遍 |
| 683 | [K Empty Slots](https://leetcode-cn.com/problems/k-empty-slots/) | | | [Java解答](code_java/src/solution/KEmptySlots.java) | | | | |
| 684 | [Redundant Connection](https://leetcode-cn.com/problems/redundant-connection/) | | | [Java解答](code_java/src/solution/RedundantConnection.java) | | | | |
| 687 | [Longest Univalue Path](https://leetcode-cn.com/problems/longest-univalue-path/) | | | [Java解答](code_java/src/solution/LongestUnivaluePath.java) | | | | |
| 695 | [Max Area of Island](https://leetcode-cn.com/problems/max-area-of-island/) | | | [Java解答](code_java/src/solution/MaxAreaOfIsland.java) | | | | |
| 703 | [Kth Largest Element in a Stream](https://leetcode-cn.com/problems/kth-largest-element-in-a-stream/) | 数据流中第K大元素 | medium | [优先级队列解法](code_java/src/solution/KthLargestElementInAStream.java) / [小根堆解法](](code_java/src/solution/KthLargestElementInAStream2.java)) | | | | 优先级队列解法/小根堆解法 |
| 771 | [Jewels and Stones](https://leetcode-cn.com/problems/jewels-and-stones/) | | | [Java解答](code_java/src/solution/JewelsAndStones.java) | | | | |
| 814 | [Binary Tree Pruning](https://leetcode-cn.com/problems/binary-tree-pruning/) | | | [Java解答](code_java/src/solution/JewelsAndStones.java) | | | | |
| 819 | [Most Common Word](https://leetcode-cn.com/problems/most-common-word/) | | | [Java解答](code_java/src/solution/MostCommonWord.java) | | | | |
| 843 | [Guess the Word](https://leetcode-cn.com/problems/guess-the-word/) | | | [Java解答](code_java/src/solution/GuessTheWord.java) | | | | |
| 844 | [Backspace String Compare](https://leetcode-cn.com/problems/backspace-string-compare/) | | | [Java解答](code_java/src/solution/BackspaceStringCompare.java) | | | | |
| 849 | [Maximize Distance to Closest Person](https://leetcode-cn.com/problems/maximize-distance-to-closest-person/) | | | [Java解答](code_java/src/solution/MaximizeDistanceToClosestPerson.java) | | | | |
| 857 | [Minimum Cost to Hire K Workers](https://leetcode-cn.com/problems/minimum-cost-to-hire-k-workers/) | | | [Java解答](code_java/src/solution/MinimumCostToHireKWorkers.java) | | | | |
| 872 | [Leaf-Similar Trees](https://leetcode-cn.com/problems/leaf-similar-trees/) | | | [Java解答](code_java/src/solution/LeafSimilarTrees.java) | | | | |
| 889 | [Construct Binary Tree from Preorder and Postorder Traversal](https://leetcode-cn.com/problems/construct-binary-tree-from-preorder-and-postorder-traversal/) | | | [Java解答](code_java/src/solution/ConstructBinaryTreeFromPreorderAndPostorderTraversal.java) | | | | |
| 904 | [Fruit Into Baskets](https://leetcode-cn.com/problems/fruit-into-baskets/) | | | [Java解答](code_java/src/solution/FruitIntoBaskets.java) | | | | |
| 929 | [Unique Email Addresses](https://leetcode-cn.com/problems/unique-email-addresses/) | | | [Java解答](code_java/src/solution/UniqueEmailAddresses.java) | | | | |