20190122

6724c95b · liu13 · 4a78cbc6 · 6724c95b · 6724c95b · 6724c95b
8 changed file
--- a/Top100.md
+++ b/Top100.md
+<img src="img/readme.png"></a>
+
+The user's favorite 100 problems are very classic. If you are a newbie, this is the best way to get started with leetcode.
+
+---
+
+用户最喜欢的100道题都是很经典的问题，是新手入门 leetcode 的最好方式。
+
+### Top 100 Liked Questions
+
+| \# | Problems | Difficulty | Solution |
+|----|----------|-----------|------|
+| 001  | [Two_Sum](https://leetcode.com/problems/two-sum/)  | Easy | [Java](./code/lc1.java)
+| 002  | [Add Two Numbers](https://leetcode.com/problems/add-two-numbers/) |Medium| [Java](./code/lc2.java)
+| 003  | [Longest Substring Without Repeating Characters](https://leetcode.com/problems/longest-substring-without-repeating-characters/) | Medium | [Java](./code/lc3.java)
+| 004  | [Median of Two Sorted Arrays](https://leetcode.com/problems/median-of-two-sorted-arrays) | Hard | [Java](./code/lc4.java)
+| 005  | [Longest Palindromic Substring](https://leetcode.com/problems/longest-palindromic-substring/) |Medium|[Java](./code/lc5.java)
+| 010  | [Regular Expression Matching](https://leetcode.com/problems/regular-expression-matching/) | Hard | [Java](./code/lc10.java)
+| 011  | [Container With Most Water](https://leetcode.com/problems/container-with-most-water/) |Medium| [Java](./code/lc11.java)
+| 015  | [3Sum](https://leetcode.com/problems/3sum/) |Medium| [Java](./code/lc15.java)
+| 017  | [Letter Combinations of a Phone Number](https://leetcode.com/problems/letter-combinations-of-a-phone-number/) |Medium| [Java](./code/lc17.java)
+| 019  | [Remove Nth Node From End of List](https://leetcode.com/problems/remove-nth-node-from-end-of-list/) | Easy | [Java](./code/lc19.java)
+| 020  | [Valid Parentheses](https://leetcode.com/problems/valid-parentheses/) | Easy | [Java](./code/lc20.java)
+| 021  | [Merge Two Sorted Lists](https://leetcode.com/problems/merge-two-sorted-lists/) | Easy | [Java](./code/lc21.java)
+| 022  | [Generate Parentheses](https://leetcode.com/problems/generate-parentheses/) |Medium| [Java](./code/lc22.java)
+| 023  | [Merge k Sorted Lists](https://leetcode.com/problems/merge-k-sorted-lists/) | Hard | [Java](./code/lc23.java)
+| 032  | [Longest Valid Parentheses](https://leetcode.com/problems/longest-valid-parentheses/) | Hard | [Java](./code/lc32.java)
+| 033  | [Search in Rotated Sorted Array](https://leetcode.com/problems/search-in-rotated-sorted-array/) |Medium| [Java](./code/lc33.java)
+| 034  | [Search for a Range](https://leetcode.com/problems/search-for-a-range/) |Medium| [Java](./code/lc34.java)
+| 035  | [Search Insert Position](https://leetcode.com/problems/search-insert-position/) |Medium| [Java](./code/lc35.java)
+| 039  | [Combination Sum](https://leetcode.com/problems/combination-sum/) |Medium| [Java](./code/lc39.java)
+| 042  | [Trapping Rain Water](https://leetcode.com/problems/trapping-rain-water/) | Hard | [Java](./code/lc42.java)
+| 046  | [Permutations](https://leetcode.com/problems/permutations/)  |Medium| [Java](./code/lc46.java)
+| 048  | [Rotate Image](https://leetcode.com/problems/rotate-image/)  |Medium| [Java](./code/lc48.java)
+| 049  | [Group Anagrams](https://leetcode.com/problems/anagrams/)|Medium| [Java](./code/lc49.java)
+| 053  | [Maximum Subarray](https://leetcode.com/problems/maximum-subarray/) |Medium| [Java](./code/lc53.java)
+| 055  | [Jump Game](https://leetcode.com/problems/jump-game/)  |Medium| [Java](./code/lc55.java)
+| 056  | [Merge Intervals](https://leetcode.com/problems/merge-intervals/) |Medium| [Java](./code/lc56.java)
+| 062  | [Unique Paths](https://leetcode.com/problems/unique-paths/)  |Medium| [Java](./code/lc62.java)
+| 064  | [Minimum Path Sum](https://leetcode.com/problems/minimum-path-sum/) |Medium| [Java](./code/lc64.java)
+| 070  | [Climbing Stairs](https://leetcode.com/problems/climbing-stairs/) | Easy | [Java](./code/lc70.java)
+| 072  | [Edit Distance](https://leetcode.com/problems/edit-distance/) | Hard | [Java](./code/lc72.java)
+| 075  | [Sort Colors](https://leetcode.com/problems/sort-colors/)|Medium| [Java](./code/lc75.java)
+| 076  | [Minimum Window Substring](https://leetcode.com/problems/minimum-window-substring) | Hard| [Java](./code/lc76.java)
+| 078  | [Subsets](https://leetcode.com/problems/subsets/) |Medium| [Java](./code/lc78.java)
+| 079  | [Word Search](https://leetcode.com/problems/word-search/)|Medium| [Java](./code/lc79.java)
+| 084  | [Largest Rectangle in Histogram](https://leetcode.com/problems/largest-rectangle-in-histogram) | Hard | [Java](./code/lc84.java)
+| 085  | [Maximal Rectangle](https://leetcode.com/problems/maximal-rectangle) | Hard |[Java](./code/lc85.java)
+| 094  | [Binary Tree Inorder Traversal](https://leetcode.com/problems/binary-tree-inorder-traversal/) |Medium| [Java](./code/lc94.java)
+| 096  | [Unique Binary Search Trees](https://leetcode.com/problems/unique-binary-search-trees/) |Medium| [Java](./code/lc96.java)
+| 098  | [Validate Binary Search Tree](https://leetcode.com/problems/validate-binary-search-tree/) |Medium| [Java](./code/lc98.java)
+| 101  | [Symmetric Tree](https://leetcode.com/problems/symmetric-tree/) | Easy | [Java](./code/lc101.java)
+| 102  | [Binary Tree Level Order Traversal](https://leetcode.com/problems/binary-tree-level-order-traversal/) | Easy | [Java](./code/lc102.java)
+| 104  | [Maximum Depth of Binary Tree](https://leetcode.com/problems/maximum-depth-of-binary-tree/) | Easy | [Java](./code/lc104.java)
+| 105  | [Construct Binary Tree from Preorder and Inorder Traversal](https://leetcode.com/problems/construct-binary-tree-from-preorder-and-inorder-traversal/) |Medium| [Java](./code/lc105.java)
+| 114  | [Flatten Binary Tree to Linked List](https://leetcode.com/problems/flatten-binary-tree-to-linked-list/) |Medium| [Java](./code/lc114.java)
+| 121  | [Best Time to Buy and Sell Stock](https://leetcode.com/problems/best-time-to-buy-and-sell-stock/) | Easy | [Java](./code/lc121.java)
+| 124  | [Binary Tree Maximum Path Sum](https://leetcode.com/problems/binary-tree-maximum-path-sum/) | Hard | [Java](./code/lc124.java)
+| 128  | [Longest Consecutive Sequence](https://leetcode.com/problems/longest-consecutive-sequence/) | Hard | [Java](./code/lc128.java)
+| 136  | [Single Number](https://leetcode.com/problems/single-number) | Easy | [Java](./code/lc136.java) 
+| 139  | [Word Break](https://leetcode.com/problems/word-break/) |Medium| [Java](./code/lc139.java)
+| 141  | [Linked List Cycle](https://leetcode.com/problems/linked-list-cycle/) | Easy | [Java](./code/lc141.java)
+| 142  | [Linked List Cycle II](https://leetcode.com/problems/linked-list-cycle-ii/) |Medium| [Java](./code/lc142.java)
+| 146  | [LRU Cache](https://leetcode.com/problems/lru-cache/)  | Hard | [Java](./code/lc146.java)
+| 148  | [Sort List](https://leetcode.com/problems/sort-list/)  |Medium| [Java](./code/lc148.java)
+| 152  | [Maximum Product Subarray](https://leetcode.com/problems/maximum-product-subarray/) |Medium| [Java](./code/lc152.java)
+| 155  | [Min Stack](https://leetcode.com/problems/min-stack/)  | Easy | [Java](./code/lc155.java)
+| 160  | [Intersection of Two Linked Lists](https://leetcode.com/problems/intersection-of-two-linked-lists/) | Easy | [Java](./code/lc160.java)
+| 169  | [Majority Element](https://leetcode.com/problems/majority-element/) | Easy | [Java](./code/lc169.java)
+| 198  | [House Robber](https://leetcode.com/problems/house-robber/)  | Easy | [Java](./code/lc198.java)
+| 200  | [Number of Islands](https://leetcode.com/problems/number-of-islands/) |Medium| [Java](./code/lc200.java)
+| 206  | [Reverse Linked List](https://leetcode.com/problems/reverse-linked-list/) | Easy |[Java](./code/lc206.java)
+| 207  | [Course Schedule](https://leetcode.com/problems/course-schedule/) |Medium|[Java](./code/lc207.java)
+| 208  | [Implement Trie (Prefix Tree)](https://leetcode.com/problems/implement-trie-prefix-tree/) |Medium| [Java](./code/lc208.java)
+| 215  | [Kth Largest Element in an Array](https://leetcode.com/problems/kth-largest-element-in-an-array/) |Medium| [Java](./code/lc215.java)
+| 221  | [Maximal Square](https://leetcode.com/problems/maximal-square/) |Medium| [Java](./code/lc221.java)
+| 226  | [Invert Binary Tree](https://leetcode.com/problems/invert-binary-tree/) | Easy | [Java](./code/lc226.java)
+| 234  | [Palindrome Linked List](https://leetcode.com/problems/palindrome-linked-list/) | Easy | [Java](./code/lc234.java)
+| 236  | [Lowest Common Ancestor of a Binary Tree](https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-tree/) |Medium| [Java](./code/lc236.java)
+| 238  | [Product of Array Except Self](https://leetcode.com/problems/product-of-array-except-self/) |Medium| [Java](./code/lc238.java)
+| 239  | [Sliding Window Maximum](https://leetcode.com/problems/sliding-window-maximum/) | Hard | [Java](./code/lc239.java)
+| 240  | [Search a 2D Matrix II](https://leetcode.com/problems/search-a-2d-matrix-ii/) |Medium| [Java](./code/lc240.java)
+| 253  | [Meeting Rooms II](https://leetcode.com/problems/meeting-rooms-ii) |Medium| 没权限
+| 279  | [Perfect Squares](https://leetcode.com/problems/perfect-squares/) |Medium| [Java](./code/lc279.java)
+| 283  | [Move Zeroes](https://leetcode.com/problems/move-zeroes/)| Easy | [Java](./code/lc283.java)
+| 287  | [Find the Duplicate Number](https://leetcode.com/problems/find-the-duplicate-number/) | Hard | [Java](./code/lc287.java)
+| 297  | [Serialize and Deserialize Binary Tree](https://leetcode.com/problems/serialize-and-deserialize-binary-tree/) | Hard | [Java](./code/lc297.java)
+| 300  | [Longest Increasing Subsequence](https://leetcode.com/problems/longest-increasing-subsequence/) |Medium| [Java](./code/lc300.java)
+| 301  | [Remove Invalid Parentheses](https://leetcode.com/problems/remove-invalid-parentheses/) |Hard| [Java](./code/lc301.java)
+| 309  | [Best Time to Buy and Sell Stock with Cooldown](https://leetcode.com/problems/best-time-to-buy-and-sell-stock-with-cooldown/) |Medium| [Java](./code/lc309.java)
+| 312  | [Burst Balloons](https://leetcode.com/problems/burst-balloons/) | Hard | [Java](./code/lc312.java)
+| 322  | [Coin Change](https://leetcode.com/problems/coin-change/)|Medium| [Java](./code/lc322.java)
+| 337  | [House Robber III](https://leetcode.com/problems/house-robber-iii/) |Medium| [Java](./code/lc337.java)
+| 338  | [Counting Bits](https://leetcode.com/problems/counting-bits/) |Medium| [Java](./code/lc338.java)
+| 347  | [Top K Frequent Elements](https://leetcode.com/problems/top-k-frequent-elements/) |Medium| [Java](./code/lc347.java)
+| 394  | [Decode String](https://leetcode.com/problems/decode-string/) |Medium| [Java](./code/lc394.java)
+| 406  | [Queue Reconstruction by Height](https://leetcode.com/problems/queue-reconstruction-by-height/) |Medium| [Java](./code/lc406.java)
+| 416  | [Partition Equal Subset Sum](https://leetcode.com/problems/partition-equal-subset-sum/) |Medium| [Java](./code/lc416.java)
+| 437  | [Path Sum III](https://leetcode.com/problems/path-sum-iii/)  | Easy |[Java](./code/lc437.java)
+| 438  | [Find All Anagrams in a String](https://leetcode.com/problems/find-all-anagrams-in-a-string/) | Easy |[Java](./code/lc438.java)
+| 448  | [Find All Numbers Disappeared in an Array](https://leetcode.com/problems/find-all-numbers-disappeared-in-an-array/) | Easy |  [Java](./code/lc448.java)
+| 461  | [Hamming Distance](https://leetcode.com/problems/hamming-distance/) | Easy |[Java](./code/lc461.java)
+| 494  | [Target Sum](https://leetcode.com/problems/target-sum/) |Medium|[Java](./code/lc494.java)
+| 538  | [Convert BST to Greater Tree](https://leetcode.com/problems/convert-bst-to-greater-tree/description/) | Easy |[Java](./code/lc538.java)
+| 543  | [Diameter of Binary Tree](https://leetcode.com/problems/diameter-of-binary-tree/description/) | Easy | [Java](./code/lc543.java)
+| 560  | [Subarray Sum Equals K](https://leetcode.com/problems/subarray-sum-equals-k) |Medium| [Java](./code/lc560.java)
+| 572  | [Subtree of Another Tree](https://leetcode.com/problems/subtree-of-another-tree/description/) | Easy | [Java](./code/lc572.java)
+| 581  | [Shortest Unsorted Continuous Subarray](https://leetcode.com/problems/shortest-unsorted-continuous-subarray/description/) | Easy | [Java](./code/lc581.java)
+| 617  | [Merge Two Binary Trees](https://leetcode.com/problems/merge-two-binary-trees/description/) | Easy | [Java](./code/lc617.java)
+| 621  | [Task Scheduler](https://leetcode.com/problems/task-scheduler) |Medium|  [Java](./code/lc621.java)
+| 647  | [Palindromic Substrings](https://leetcode.com/problems/palindromic-substrings) |Medium|[Java](./code/lc647.java)
+| 771  | [Jewels and Stones](https://leetcode.com/problems/jewels-and-stones/) |Easy|[Java](./code/lc771.java)
--- a/TopInterview.md
+++ b/TopInterview.md
+### Top Interview Questions
+
+
+| \# | Problems | Difficulty | Solution |
+|----|----------|-----------|------|
+| 001  | [Two_Sum](https://leetcode.com/problems/two-sum/)  | Easy | [Java](./code/lc1.java)
+| 002  | [Add Two Numbers](https://leetcode.com/problems/add-two-numbers/) |Medium| [Java](./code/lc2.java)
+| 003  | [Longest Substring Without Repeating Characters](https://leetcode.com/problems/longest-substring-without-repeating-characters/) | Medium | [Java](./code/lc3.java)
+| 004  | [Median of Two Sorted Arrays](https://leetcode.com/problems/median-of-two-sorted-arrays) | Hard | [Java](./code/lc4.java)
+| 005  | [Longest Palindromic Substring](https://leetcode.com/problems/longest-palindromic-substring/) |Medium|[Java](./code/lc5.java)
+
+
+| 010  | [Regular Expression Matching](https://leetcode.com/problems/regular-expression-matching/) | Hard | [Java](./code/lc10.java)
+| 011  | [Container With Most Water](https://leetcode.com/problems/container-with-most-water/) |Medium| [Java](./code/lc11.java)
+
+
+| 015  | [3Sum](https://leetcode.com/problems/3sum/) |Medium| [Java](./code/lc15.java)
+| 017  | [Letter Combinations of a Phone Number](https://leetcode.com/problems/letter-combinations-of-a-phone-number/) |Medium| [Java](./code/lc17.java)
+| 019  | [Remove Nth Node From End of List](https://leetcode.com/problems/remove-nth-node-from-end-of-list/) | Easy | [Java](./code/lc19.java)
+| 020  | [Valid Parentheses](https://leetcode.com/problems/valid-parentheses/) | Easy | [Java](./code/lc20.java)
+| 021  | [Merge Two Sorted Lists](https://leetcode.com/problems/merge-two-sorted-lists/) | Easy | [Java](./code/lc21.java)
+| 022  | [Generate Parentheses](https://leetcode.com/problems/generate-parentheses/) |Medium| [Java](./code/lc22.java)
+| 023  | [Merge k Sorted Lists](https://leetcode.com/problems/merge-k-sorted-lists/) | Hard | [Java](./code/lc23.java)
+
+
+| 033  | [Search in Rotated Sorted Array](https://leetcode.com/problems/search-in-rotated-sorted-array/) |Medium| [Java](./code/lc33.java)
+| 034  | [Search for a Range](https://leetcode.com/problems/search-for-a-range/) |Medium| [Java](./code/lc34.java)
+| 035  | [Search Insert Position](https://leetcode.com/problems/search-insert-position/) |Medium| [Java](./code/lc35.java)
+
+
+
+| 042  | [Trapping Rain Water](https://leetcode.com/problems/trapping-rain-water/) | Hard | [Java](./code/lc42.java)
+
+| 046  | [Permutations](https://leetcode.com/problems/permutations/)  |Medium| [Java](./code/lc46.java)
+| 048  | [Rotate Image](https://leetcode.com/problems/rotate-image/)  |Medium| [Java](./code/lc48.java)
+| 049  | [Group Anagrams](https://leetcode.com/problems/anagrams/)|Medium| [Java](./code/lc49.java)
+
+| 053  | [Maximum Subarray](https://leetcode.com/problems/maximum-subarray/) |Medium| [Java](./code/lc53.java)
+
+| 055  | [Jump Game](https://leetcode.com/problems/jump-game/)  |Medium| [Java](./code/lc55.java)
+| 056  | [Merge Intervals](https://leetcode.com/problems/merge-intervals/) |Medium| [Java](./code/lc56.java)
+| 062  | [Unique Paths](https://leetcode.com/problems/unique-paths/)  |Medium| [Java](./code/lc62.java)
+
+
+| 070  | [Climbing Stairs](https://leetcode.com/problems/climbing-stairs/) | Easy | [Java](./code/lc70.java)
+
+| 075  | [Sort Colors](https://leetcode.com/problems/sort-colors/)|Medium| [Java](./code/lc75.java)
+| 076  | [Minimum Window Substring](https://leetcode.com/problems/minimum-window-substring) | Hard| [Java](./code/lc76.java)
+| 078  | [Subsets](https://leetcode.com/problems/subsets/) |Medium| [Java](./code/lc78.java)
+| 079  | [Word Search](https://leetcode.com/problems/word-search/)|Medium| [Java](./code/lc79.java)
+| 084  | [Largest Rectangle in Histogram](https://leetcode.com/problems/largest-rectangle-in-histogram) | Hard | [Java](./code/lc84.java)
+
+
+| 094  | [Binary Tree Inorder Traversal](https://leetcode.com/problems/binary-tree-inorder-traversal/) |Medium| [Java](./code/lc94.java)
+
+| 098  | [Validate Binary Search Tree](https://leetcode.com/problems/validate-binary-search-tree/) |Medium| [Java](./code/lc98.java)
+| 101  | [Symmetric Tree](https://leetcode.com/problems/symmetric-tree/) | Easy | [Java](./code/lc101.java)
+| 102  | [Binary Tree Level Order Traversal](https://leetcode.com/problems/binary-tree-level-order-traversal/) | Easy | [Java](./code/lc102.java)
+
+| 104  | [Maximum Depth of Binary Tree](https://leetcode.com/problems/maximum-depth-of-binary-tree/) | Easy | [Java](./code/lc104.java)
+| 105  | [Construct Binary Tree from Preorder and Inorder Traversal](https://leetcode.com/problems/construct-binary-tree-from-preorder-and-inorder-traversal/) |Medium| [Java](./code/lc105.java)
+
+
+
+
+| 121  | [Best Time to Buy and Sell Stock](https://leetcode.com/problems/best-time-to-buy-and-sell-stock/) | Easy | [Java](./code/lc121.java)
+
+| 124  | [Binary Tree Maximum Path Sum](https://leetcode.com/problems/binary-tree-maximum-path-sum/) | Hard | [Java](./code/lc124.java)
+
+
+| 128  | [Longest Consecutive Sequence](https://leetcode.com/problems/longest-consecutive-sequence/) | Hard | [Java](./code/lc128.java)
+
+
+
+| 136  | [Single Number](https://leetcode.com/problems/single-number) | Easy | [Java](./code/lc136.java) 
+
+| 139  | [Word Break](https://leetcode.com/problems/word-break/) |Medium| [Java](./code/lc139.java)
+
+| 141  | [Linked List Cycle](https://leetcode.com/problems/linked-list-cycle/) | Easy | [Java](./code/lc141.java)
+
+| 146  | [LRU Cache](https://leetcode.com/problems/lru-cache/)  | Hard | [Java](./code/lc146.java)
+| 148  | [Sort List](https://leetcode.com/problems/sort-list/)  |Medium| [Java](./code/lc148.java)
+
+
+
+| 152  | [Maximum Product Subarray](https://leetcode.com/problems/maximum-product-subarray/) |Medium| [Java](./code/lc152.java)
+| 155  | [Min Stack](https://leetcode.com/problems/min-stack/)  | Easy | [Java](./code/lc155.java)
+| 160  | [Intersection of Two Linked Lists](https://leetcode.com/problems/intersection-of-two-linked-lists/) | Easy | [Java](./code/lc160.java)
+
+
+
+
+| 169  | [Majority Element](https://leetcode.com/problems/majority-element/) | Easy | [Java](./code/lc169.java)
+| 198  | [House Robber](https://leetcode.com/problems/house-robber/)  | Easy | [Java](./code/lc198.java)
+| 200  | [Number of Islands](https://leetcode.com/problems/number-of-islands/) |Medium| [Java](./code/lc200.java)
+
+
+| 206  | [Reverse Linked List](https://leetcode.com/problems/reverse-linked-list/) | Easy |[Java](./code/lc206.java)
+| 207  | [Course Schedule](https://leetcode.com/problems/course-schedule/) |Medium|[Java](./code/lc207.java)
+| 208  | [Implement Trie (Prefix Tree)](https://leetcode.com/problems/implement-trie-prefix-tree/) |Medium| [Java](./code/lc208.java)
+
+
+
+| 215  | [Kth Largest Element in an Array](https://leetcode.com/problems/kth-largest-element-in-an-array/) |Medium| [Java](./code/lc215.java)
+
+
+
+| 234  | [Palindrome Linked List](https://leetcode.com/problems/palindrome-linked-list/) | Easy | [Java](./code/lc234.java)
+| 236  | [Lowest Common Ancestor of a Binary Tree](https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-tree/) |Medium| [Java](./code/lc236.java)
+
+| 238  | [Product of Array Except Self](https://leetcode.com/problems/product-of-array-except-self/) |Medium| [Java](./code/lc238.java)
+| 239  | [Sliding Window Maximum](https://leetcode.com/problems/sliding-window-maximum/) | Hard | [Java](./code/lc239.java)
+| 240  | [Search a 2D Matrix II](https://leetcode.com/problems/search-a-2d-matrix-ii/) |Medium| [Java](./code/lc240.java)
+
+
+| 279  | [Perfect Squares](https://leetcode.com/problems/perfect-squares/) |Medium| [Java](./code/lc279.java)
+| 283  | [Move Zeroes](https://leetcode.com/problems/move-zeroes/)| Easy | [Java](./code/lc283.java)
+
+| 287  | [Find the Duplicate Number](https://leetcode.com/problems/find-the-duplicate-number/) | Hard | [Java](./code/lc287.java)
+
+
+| 297  | [Serialize and Deserialize Binary Tree](https://leetcode.com/problems/serialize-and-deserialize-binary-tree/) | Hard | [Java](./code/lc297.java)
+| 300  | [Longest Increasing Subsequence](https://leetcode.com/problems/longest-increasing-subsequence/) |Medium| [Java](./code/lc300.java)
+
+
+| 322  | [Coin Change](https://leetcode.com/problems/coin-change/)|Medium| [Java](./code/lc322.java)
+
+
+
+
+
+
+| 337  | [House Robber III](https://leetcode.com/problems/house-robber-iii/) |Medium| [Java](./code/lc337.java)
+| 347  | [Top K Frequent Elements](https://leetcode.com/problems/top-k-frequent-elements/) |Medium| [Java](./code/lc347.java)
--- a/code/lc543.java
+++ b/code/lc543.java
+package code;
+/*
+ * 543. Diameter of Binary Tree
+ * 题意：树种的最长路径
+ * 难度：Easy
+ * 分类：Tree
+ * 思路：和lc124思路一样，但lc124是Hard，这道竟然是Easy，哈哈哈
+ * Tips：
+ */
+public class lc543 {
+    public class TreeNode {
+        int val;
+        TreeNode left;
+        TreeNode right;
+        TreeNode(int x) { val = x; }
+    }
+    int max = 0;
+    public int diameterOfBinaryTree(TreeNode root) {
+        helper(root);
+        return max;
+    }
+    public int helper(TreeNode root){
+        if(root==null)
+            return 0;
+        int left = helper(root.left);
+        int right = helper(root.right);
+        max = Math.max(left+right, max);
+        return Math.max(left, right)+1;
+    }
+}
--- a/code/lc572.java
+++ b/code/lc572.java
+package code;
+/*
+ * 572. Subtree of Another Tree
+ * 题意：判断一棵树是否为另外一棵树的子树
+ * 难度：Easy
+ * 分类：Tree
+ * 思路：两种方法，一种是先序遍历，然后比较字符串即可，注意每个节点开始前加个字符，null也要加进去。
+ *      另一种递归的方法。
+ * Tips：
+ */
+public class lc572 {
+    public class TreeNode {
+        int val;
+        TreeNode left;
+        TreeNode right;
+        TreeNode(int x) { val = x; }
+    }
+
+    public boolean isSubtree(TreeNode s, TreeNode t) {
+        if (s == null) return false;
+        return helper(s,t) || isSubtree(s.left,t) ||isSubtree(s.right,t);   // 注意递归方法的不同，是调用哪个函数
+    }
+    public boolean helper(TreeNode s, TreeNode t){
+        if( s==null && t==null ) return true;
+        if( s==null || t==null || s.val!=t.val ) return false;
+        return helper(s.left, t.left) && helper(s.right, t.right);
+    }
+
+    public boolean isSubtree2(TreeNode s, TreeNode t) {
+        StringBuilder tree1 = new StringBuilder();
+        StringBuilder tree2 = new StringBuilder();
+        helper2(s, tree1);
+        helper2(s, tree2);
+        return tree1.toString().contains(tree2.toString());
+    }
+    public void helper2(TreeNode node, StringBuilder res){
+        if(node==null)
+            res.append(",#");   //先放','表示一个新节点的开始，#代表null
+        else {
+            res.append( ","+node.val );
+            helper2(node.left, res);
+            helper2(node.right, res);
+        }
+    }
+
+}
--- a/code/lc581.java
+++ b/code/lc581.java
+package code;
+/*
+ * 581. Shortest Unsorted Continuous Subarray
+ * 题意：找出数组中需要排序的长度
+ * 难度：Easy
+ * 分类：Array
+ * 思路：
+ * Tips：直接写出来的
+ */
+public class lc581 {
+    public int findUnsortedSubarray(int[] nums) {
+        if(nums.length<2)
+            return 0;
+        int left =0, right = 0;
+        int temp = nums[nums.length-1];
+        for (int i = nums.length-2; i >=0 ; i--) {
+            if(nums[i]>temp) left = i;          //小于最小值就不用排序了，大于的话记录一下
+            if(nums[i]<temp) temp = nums[i];    //记录最小值
+        }
+        temp = nums[0];
+        for (int i = 1; i < nums.length ; i++) {
+            if(nums[i]<temp) right = i;     //找right
+            if(nums[i]>temp) temp = nums[i];
+        }
+        return left==right? 0 : right-left+1;
+    }
+}
--- a/code/lc617.java
+++ b/code/lc617.java
+package code;
+/*
+ * 617. Merge Two Binary Trees
+ * 题意：合并两个二叉树
+ * 难度：Easy
+ * 分类：Tree
+ * 思路：递归的方法
+ * Tips：对比下自己的代码和别人的代码，为什么别人的更简洁。自己的思路还是有些乱，应该先想清楚递归的子问题，再开始写。
+ *       想明白了再写，不要修修补补的。
+ */
+public class lc617 {
+    public class TreeNode {
+        int val;
+        TreeNode left;
+        TreeNode right;
+        TreeNode(int x) { val = x; }
+    }
+    public TreeNode mergeTrees(TreeNode t1, TreeNode t2) {
+        if(t1==null) return t2;
+        if(t2==null) return t1;
+        if(t1!=null && t2!=null) t1.val = t1.val + t2.val;
+        helper(t1, t2);
+        return t1;
+    }
+    public void helper(TreeNode t1, TreeNode t2){
+        if(t1.left==null) {
+            t1.left = t2.left;
+            return;
+        }
+        if(t1.right==null) {
+            t1.right = t2.right;
+            return;
+        }
+        if( t1.left!=null && t2.left!=null ) {
+            t1.left.val = t1.left.val + t2.left.val;
+            helper(t1.left, t2.left);
+        }
+        if( t1.right!=null && t2.right!=null ) {
+            t1.right.val = t1.right.val + t2.right.val;
+            helper(t1.right, t2.right);
+        }
+    }
+
+    public TreeNode mergeTrees2(TreeNode t1, TreeNode t2) {
+        if (t1 == null)
+            return t2;
+        if (t2 == null)
+            return t1;
+        t1.val += t2.val;
+        t1.left = mergeTrees(t1.left, t2.left);
+        t1.right = mergeTrees(t1.right, t2.right);
+        return t1;
+    }
+}
--- a/code/lc771.java
+++ b/code/lc771.java
+package code;
+/*
+ * 771. Jewels and Stones
+ * 题意：S中出现的字符，在J中也出现的个数
+ * 难度：Easy
+ * 分类：Hash Table
+ * 思路：
+ * Tips：
+ */
+public class lc771 {
+    public int numJewelsInStones(String J, String S) {
+        int res=0;
+        for(char c : S.toCharArray()){
+            if(J.indexOf(c) != -1){
+                res++;
+            }
+        }
+        return res;
+    }
+}
--- a/readme.md
+++ b/readme.md
-LeetCode Top 100 Liked Questions
+LeetCode Problems I have Soved
 ===
-<img src="img/readme.png"></a>
-
-The user's favorite 100 problems are very classic. If you are a newbie, this is the best way to get started with leetcode.

 Language: Java

@@ -11,7 +8,7 @@ Welcome to improve this project with me.*

 ---

-用户最喜欢的100道题都是很经典的问题，是新手入门 leetcode 的最好方式。**每道题在代码头部都添加了我的解题思路和想法，希望对你有用**。
+**每道题在代码头部都添加了我的解题思路和想法，希望对你有用**。

 语言: Java

@@ -19,107 +16,126 @@ Welcome to improve this project with me.*

 ---

-### Top 100 Liked Questions
+用户最喜欢的100道题
+[Top 100 Liked Questions](./Top100.md)
+
+面试最容易被问到的题（更新中...）
+[Top Interview Questions](./TopInterview.md)
+

-| \# | Problems | Difficulty | Solution |
-|----|----------|-----------|------|
-| 001  | [Two_Sum](https://leetcode.com/problems/two-sum/)  | Easy | [Java](./code/lc1.java)
-| 002  | [Add Two Numbers](https://leetcode.com/problems/add-two-numbers/) |Medium| [Java](./code/lc2.java)
-| 003  | [Longest Substring Without Repeating Characters](https://leetcode.com/problems/longest-substring-without-repeating-characters/) | Medium | [Java](./code/lc3.java)
-| 004  | [Median of Two Sorted Arrays](https://leetcode.com/problems/median-of-two-sorted-arrays) | Hard | [Java](./code/lc4.java)
-| 005  | [Longest Palindromic Substring](https://leetcode.com/problems/longest-palindromic-substring/) |Medium|[Java](./code/lc5.java)
-| 010  | [Regular Expression Matching](https://leetcode.com/problems/regular-expression-matching/) | Hard | [Java](./code/lc10.java)
-| 011  | [Container With Most Water](https://leetcode.com/problems/container-with-most-water/) |Medium| [Java](./code/lc11.java)
-| 015  | [3Sum](https://leetcode.com/problems/3sum/) |Medium| [Java](./code/lc15.java)
-| 017  | [Letter Combinations of a Phone Number](https://leetcode.com/problems/letter-combinations-of-a-phone-number/) |Medium| [Java](./code/lc17.java)
-| 019  | [Remove Nth Node From End of List](https://leetcode.com/problems/remove-nth-node-from-end-of-list/) | Easy | [Java](./code/lc19.java)
-| 020  | [Valid Parentheses](https://leetcode.com/problems/valid-parentheses/) | Easy | [Java](./code/lc20.java)
-| 021  | [Merge Two Sorted Lists](https://leetcode.com/problems/merge-two-sorted-lists/) | Easy | [Java](./code/lc21.java)
-| 022  | [Generate Parentheses](https://leetcode.com/problems/generate-parentheses/) |Medium| [Java](./code/lc22.java)
-| 023  | [Merge k Sorted Lists](https://leetcode.com/problems/merge-k-sorted-lists/) | Hard | [Java](./code/lc23.java)
-| 032  | [Longest Valid Parentheses](https://leetcode.com/problems/longest-valid-parentheses/) | Hard | [Java](./code/lc32.java)
-| 033  | [Search in Rotated Sorted Array](https://leetcode.com/problems/search-in-rotated-sorted-array/) |Medium| [Java](./code/lc33.java)
-| 034  | [Search for a Range](https://leetcode.com/problems/search-for-a-range/) |Medium| [Java](./code/lc34.java)
-| 035  | [Search Insert Position](https://leetcode.com/problems/search-insert-position/) |Medium| [Java](./code/lc35.java)
-| 039  | [Combination Sum](https://leetcode.com/problems/combination-sum/) |Medium| [Java](./code/lc39.java)
-| 042  | [Trapping Rain Water](https://leetcode.com/problems/trapping-rain-water/) | Hard | [Java](./code/lc42.java)
-| 046  | [Permutations](https://leetcode.com/problems/permutations/)  |Medium| [Java](./code/lc46.java)
-| 048  | [Rotate Image](https://leetcode.com/problems/rotate-image/)  |Medium| [Java](./code/lc48.java)
-| 049  | [Group Anagrams](https://leetcode.com/problems/anagrams/)|Medium| [Java](./code/lc49.java)
-| 053  | [Maximum Subarray](https://leetcode.com/problems/maximum-subarray/) |Medium| [Java](./code/lc53.java)
-| 055  | [Jump Game](https://leetcode.com/problems/jump-game/)  |Medium| [Java](./code/lc55.java)
-| 056  | [Merge Intervals](https://leetcode.com/problems/merge-intervals/) |Medium| [Java](./code/lc56.java)
-| 062  | [Unique Paths](https://leetcode.com/problems/unique-paths/)  |Medium| [Java](./code/lc62.java)
-| 064  | [Minimum Path Sum](https://leetcode.com/problems/minimum-path-sum/) |Medium| [Java](./code/lc64.java)
-| 070  | [Climbing Stairs](https://leetcode.com/problems/climbing-stairs/) | Easy | [Java](./code/lc70.java)
-| 072  | [Edit Distance](https://leetcode.com/problems/edit-distance/) | Hard | [Java](./code/lc72.java)
-| 075  | [Sort Colors](https://leetcode.com/problems/sort-colors/)|Medium| [Java](./code/lc75.java)
-| 076  | [Minimum Window Substring](https://leetcode.com/problems/minimum-window-substring) | Hard| [Java](./code/lc76.java)
-| 078  | [Subsets](https://leetcode.com/problems/subsets/) |Medium| [Java](./code/lc78.java)
-| 079  | [Word Search](https://leetcode.com/problems/word-search/)|Medium| [Java](./code/lc79.java)
-| 084  | [Largest Rectangle in Histogram](https://leetcode.com/problems/largest-rectangle-in-histogram) | Hard | [Java](./code/lc84.java)
-| 085  | [Maximal Rectangle](https://leetcode.com/problems/maximal-rectangle) | Hard |[Java](./code/lc85.java)
-| 094  | [Binary Tree Inorder Traversal](https://leetcode.com/problems/binary-tree-inorder-traversal/) |Medium| [Java](./code/lc94.java)
-| 096  | [Unique Binary Search Trees](https://leetcode.com/problems/unique-binary-search-trees/) |Medium| [Java](./code/lc96.java)
-| 098  | [Validate Binary Search Tree](https://leetcode.com/problems/validate-binary-search-tree/) |Medium| [Java](./code/lc98.java)
-| 100  | [Same Tree](https://leetcode.com/problems/same-tree/)  | Easy | [Java](./code/lc100.java)
-| 101  | [Symmetric Tree](https://leetcode.com/problems/symmetric-tree/) | Easy | [Java](./code/lc101.java)
-| 102  | [Binary Tree Level Order Traversal](https://leetcode.com/problems/binary-tree-level-order-traversal/) | Easy | [Java](./code/lc102.java)
-| 104  | [Maximum Depth of Binary Tree](https://leetcode.com/problems/maximum-depth-of-binary-tree/) | Easy | [Java](./code/lc104.java)
-| 105  | [Construct Binary Tree from Preorder and Inorder Traversal](https://leetcode.com/problems/construct-binary-tree-from-preorder-and-inorder-traversal/) |Medium| [Java](./code/lc105.java)
-| 114  | [Flatten Binary Tree to Linked List](https://leetcode.com/problems/flatten-binary-tree-to-linked-list/) |Medium| [Java](./code/lc114.java)
-| 121  | [Best Time to Buy and Sell Stock](https://leetcode.com/problems/best-time-to-buy-and-sell-stock/) | Easy | [Java](./code/lc121.java)
-| 124  | [Binary Tree Maximum Path Sum](https://leetcode.com/problems/binary-tree-maximum-path-sum/) | Hard | [Java](./code/lc124.java)
-| 128  | [Longest Consecutive Sequence](https://leetcode.com/problems/longest-consecutive-sequence/) | Hard | [Java](./code/lc128.java)
-| 136  | [Single Number](https://leetcode.com/problems/single-number) | Easy | [Java](./code/lc136.java) 
-| 139  | [Word Break](https://leetcode.com/problems/word-break/) |Medium| [Java](./code/lc139.java)
-| 141  | [Linked List Cycle](https://leetcode.com/problems/linked-list-cycle/) | Easy | [Java](./code/lc141.java)
-| 142  | [Linked List Cycle II](https://leetcode.com/problems/linked-list-cycle-ii/) |Medium| [Java](./code/lc142.java)
-| 146  | [LRU Cache](https://leetcode.com/problems/lru-cache/)  | Hard | [Java](./code/lc146.java)
-| 148  | [Sort List](https://leetcode.com/problems/sort-list/)  |Medium| [Java](./code/lc148.java)
-| 152  | [Maximum Product Subarray](https://leetcode.com/problems/maximum-product-subarray/) |Medium| [Java](./code/lc152.java)
-| 155  | [Min Stack](https://leetcode.com/problems/min-stack/)  | Easy | [Java](./code/lc155.java)
-| 160  | [Intersection of Two Linked Lists](https://leetcode.com/problems/intersection-of-two-linked-lists/) | Easy | [Java](./code/lc160.java)
-| 169  | [Majority Element](https://leetcode.com/problems/majority-element/) | Easy | [Java](./code/lc169.java)
-| 198  | [House Robber](https://leetcode.com/problems/house-robber/)  | Easy | [Java](./code/lc198.java)
-| 200  | [Number of Islands](https://leetcode.com/problems/number-of-islands/) |Medium| [Java](./code/lc200.java)
-| 206  | [Reverse Linked List](https://leetcode.com/problems/reverse-linked-list/) | Easy |[Java](./code/lc206.java)
-| 207  | [Course Schedule](https://leetcode.com/problems/course-schedule/) |Medium|[Java](./code/lc207.java)
-| 208  | [Implement Trie (Prefix Tree)](https://leetcode.com/problems/implement-trie-prefix-tree/) |Medium| [Java](./code/lc208.java)
-| 215  | [Kth Largest Element in an Array](https://leetcode.com/problems/kth-largest-element-in-an-array/) |Medium| [Java](./code/lc215.java)
-| 221  | [Maximal Square](https://leetcode.com/problems/maximal-square/) |Medium| [Java](./code/lc221.java)
-| 226  | [Invert Binary Tree](https://leetcode.com/problems/invert-binary-tree/) | Easy | [Java](./code/lc226.java)
-| 234  | [Palindrome Linked List](https://leetcode.com/problems/palindrome-linked-list/) | Easy | [Java](./code/lc234.java)
-| 236  | [Lowest Common Ancestor of a Binary Tree](https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-tree/) |Medium| [Java](./code/lc236.java)
-| 238  | [Product of Array Except Self](https://leetcode.com/problems/product-of-array-except-self/) |Medium| [Java](./code/lc238.java)
-| 239  | [Sliding Window Maximum](https://leetcode.com/problems/sliding-window-maximum/) | Hard | [Java](./code/lc239.java)
-| 240  | [Search a 2D Matrix II](https://leetcode.com/problems/search-a-2d-matrix-ii/) |Medium| [Java](./code/lc240.java)
-| 279  | [Perfect Squares](https://leetcode.com/problems/perfect-squares/) |Medium| [Java](./code/lc279.java)
-| 283  | [Move Zeroes](https://leetcode.com/problems/move-zeroes/)| Easy | [Java](./code/lc283.java)
-| 287  | [Find the Duplicate Number](https://leetcode.com/problems/find-the-duplicate-number/) | Hard | [Java](./code/lc287.java)
-| 297  | [Serialize and Deserialize Binary Tree](https://leetcode.com/problems/serialize-and-deserialize-binary-tree/) | Hard | [Java](./code/lc297.java)
-| 300  | [Longest Increasing Subsequence](https://leetcode.com/problems/longest-increasing-subsequence/) |Medium| [Java](./code/lc300.java)
-| 301  | [Remove Invalid Parentheses](https://leetcode.com/problems/remove-invalid-parentheses/) |Hard| [Java](./code/lc301.java)
-| 309  | [Best Time to Buy and Sell Stock with Cooldown](https://leetcode.com/problems/best-time-to-buy-and-sell-stock-with-cooldown/) |Medium| [Java](./code/lc309.java)
-| 312  | [Burst Balloons](https://leetcode.com/problems/burst-balloons/) | Hard | [Java](./code/lc312.java)
-| 322  | [Coin Change](https://leetcode.com/problems/coin-change/)|Medium| [Java](./code/lc322.java)
-| 337  | [House Robber III](https://leetcode.com/problems/house-robber-iii/) |Medium| [Java](./code/lc337.java)
-| 338  | [Counting Bits](https://leetcode.com/problems/counting-bits/) |Medium| [Java](./code/lc338.java)
-| 347  | [Top K Frequent Elements](https://leetcode.com/problems/top-k-frequent-elements/) |Medium| [Java](./code/lc347.java)
-| 394  | [Decode String](https://leetcode.com/problems/decode-string/) |Medium| [Java](./code/lc394.java)
-| 406  | [Queue Reconstruction by Height](https://leetcode.com/problems/queue-reconstruction-by-height/) |Medium| [Java](./code/lc406.java)
-| 416  | [Partition Equal Subset Sum](https://leetcode.com/problems/partition-equal-subset-sum/) |Medium| [Java](./code/lc416.java)
-| 437  | [Path Sum III](https://leetcode.com/problems/path-sum-iii/)  | Easy |[Java](./code/lc437.java)
-| 438  | [Find All Anagrams in a String](https://leetcode.com/problems/find-all-anagrams-in-a-string/) | Easy |[Java](./code/lc438.java)
-| 448  | [Find All Numbers Disappeared in an Array](https://leetcode.com/problems/find-all-numbers-disappeared-in-an-array/) | Easy |  [Java]
-| 461  | [Hamming Distance](https://leetcode.com/problems/hamming-distance/) | Easy |[Java](./code/lc494.java)
-| 494  | [Target Sum](https://leetcode.com/problems/target-sum/) |Medium|[Java]
-| 538  | [Convert BST to Greater Tree](https://leetcode.com/problems/convert-bst-to-greater-tree/description/) | Easy |[Java]
-| 543  | [Diameter of Binary Tree](https://leetcode.com/problems/diameter-of-binary-tree/description/) | Easy | [Java]
-| 560  | [Subarray Sum Equals K](https://leetcode.com/problems/subarray-sum-equals-k) |Medium| [Java](./code/lc560.java)
-| 572  | [Subtree of Another Tree](https://leetcode.com/problems/subtree-of-another-tree/description/) | Easy | [Java]
-| 581  | [Shortest Unsorted Continuous Subarray](https://leetcode.com/problems/shortest-unsorted-continuous-subarray/description/) | Easy | [Java]
-| 617  | [Merge Two Binary Trees](https://leetcode.com/problems/merge-two-binary-trees/description/) | Easy | [Java]
-| 621  | [Task Scheduler](https://leetcode.com/problems/task-scheduler) |Medium|  [Java](./code/lc621.java)
-| 647  | [Palindromic Substrings](https://leetcode.com/problems/palindromic-substrings) |Medium|[Java](./code/lc647.java)
+### LeetCode Problems I have Soved

+| \# | Solution |
+|----|------|
+| 001  | [Java](./code/lc1.java)
+| 002  | [Java](./code/lc2.java)
+| 003  | [Java](./code/lc3.java)
+| 004  | [Java](./code/lc4.java)
+| 005  | [Java](./code/lc5.java)
+| 007  | [Java](./code/lc7.java)
+| 008  | [Java](./code/lc8.java)
+| 010  | [Java](./code/lc10.java)
+| 011  | [Java](./code/lc11.java)
+| 013  | [Java](./code/lc13java)
+| 014  | [Java](./code/lc14java)
+| 015  | [Java](./code/lc15java)
+| 017  | [Java](./code/lc17.java)
+| 019  | [Java](./code/lc19.java)
+| 020  | [Java](./code/lc20.java)
+| 021  | [Java](./code/lc21.java)
+| 022  | [Java](./code/lc22.java)
+| 023  | [Java](./code/lc23.java)
+| 026  | [Java](./code/lc26.java)
+| 028  | [Java](./code/lc28.java)
+| 031  | [Java](./code/lc31.java)
+| 032  | [Java](./code/lc32.java)
+| 033  | [Java](./code/lc33.java)
+| 034  | [Java](./code/lc34.java)
+| 038  | [Java](./code/lc38.java)
+| 039  | [Java](./code/lc39.java)
+| 042  | [Java](./code/lc42.java)
+| 046  | [Java](./code/lc46.java)
+| 048  | [Java](./code/lc48.java)
+| 049  | [Java](./code/lc49.java)
+| 053  | [Java](./code/lc53.java)
+| 055  | [Java](./code/lc55.java)
+| 056  | [Java](./code/lc56.java)
+| 058  | [Java](./code/lc58.java)
+| 062  | [Java](./code/lc62.java)
+| 063  | [Java](./code/lc63.java)
+| 064  | [Java](./code/lc64.java)
+| 066  | [Java](./code/lc66.java)
+| 069  | [Java](./code/lc69.java)
+| 070  | [Java](./code/lc70.java)
+| 072  | [Java](./code/lc72.java)
+| 075  | [Java](./code/lc75.java)
+| 076  | [Java](./code/lc76.java)
+| 078  | [Java](./code/lc78.java)
+| 079  | [Java](./code/lc79.java)
+| 084  | [Java](./code/lc84.java)
+| 085  | [Java](./code/lc85.java)
+| 088  | [Java](./code/lc88.java)
+| 094  | [Java](./code/lc94.java)
+| 096  | [Java](./code/lc96.java)
+| 098  | [Java](./code/lc98.java)
+| 101  | [Java](./code/lc101.java)
+| 102  | [Java](./code/lc102.java)
+| 104  | [Java](./code/lc104.java)
+| 105  | [Java](./code/lc105.java)
+| 114  | [Java](./code/lc114.java)
+| 121  | [Java](./code/lc121.java)
+| 122  | [Java](./code/lc122.java)
+| 124  | [Java](./code/lc124.java)
+| 128  | [Java](./code/lc128.java)
+| 136  | [Java](./code/lc136.java)
+| 139  | [Java](./code/lc139.java)
+| 141  | [Java](./code/lc141.java)
+| 142  | [Java](./code/lc142.java)
+| 144  | [Java](./code/lc144.java)
+| 145  | [Java](./code/lc145.java)
+| 146  | [Java](./code/lc146.java)
+| 148  | [Java](./code/lc148.java)
+| 152  | [Java](./code/lc152.java)
+| 155  | [Java](./code/lc155.java)
+| 160  | [Java](./code/lc160.java)
+| 169  | [Java](./code/lc169.java)
+| 198  | [Java](./code/lc198.java)
+| 200  | [Java](./code/lc200.java)
+| 206  | [Java](./code/lc206.java)
+| 207  | [Java](./code/lc207.java)
+| 208  | [Java](./code/lc208.java)
+| 215  | [Java](./code/lc215.java)
+| 221  | [Java](./code/lc221.java)
+| 226  | [Java](./code/lc226.java)
+| 234  | [Java](./code/lc234.java)
+| 238  | [Java](./code/lc238.java)
+| 239  | [Java](./code/lc239.java)
+| 240  | [Java](./code/lc240.java)
+| 279  | [Java](./code/lc279.java)
+| 283  | [Java](./code/lc283.java)
+| 287  | [Java](./code/lc287.java)
+| 297  | [Java](./code/lc297.java)
+| 300  | [Java](./code/lc300.java)
+| 301  | [Java](./code/lc301.java)
+| 309  | [Java](./code/lc309.java)
+| 312  | [Java](./code/lc312.java)
+| 322  | [Java](./code/lc322.java)
+| 337  | [Java](./code/lc337.java)
+| 338  | [Java](./code/lc338.java)
+| 347  | [Java](./code/lc347.java)
+| 394  | [Java](./code/lc394.java)
+| 406  | [Java](./code/lc406.java)
+| 416  | [Java](./code/lc416.java)
+| 437  | [Java](./code/lc437.java)
+| 438  | [Java](./code/lc438.java)
+| 448  | [Java](./code/lc448.java)
+| 461  | [Java](./code/lc461.java)
+| 494  | [Java](./code/lc494.java)
+| 538  | [Java](./code/lc538.java)
+| 543  | [Java](./code/lc543.java)
+| 572  | [Java](./code/lc572.java)
+| 581  | [Java](./code/lc581.java)
+| 617  | [Java](./code/lc617.java)
+| 621  | [Java](./code/lc621.java)
+| 647  | [Java](./code/lc647.java)
+| 771  | [Java](./code/lc771.java)