组队复习算法+刷题

08/20 （Day4)
玩了两天 回来补一下
130. Surrounded Regions Medium 和#islands很像 dfs
5. Longest Palindromic Substring -medium 用了两种方法 dp很好想，但贼慢，用skip duplicate char的方法很好用 s.substr(start, length)可以截取substring， vector<vector<int>>ans(width,vector<in>(height, 0)); 可以initialize 2d array
516 Longest Palindromic Subsequence -medium dp

顶啊！楼主考不考虑弄个微信群方便交流？

8/21
103.binary-tree-zigzag-level-order-traversal.java
239.sliding-window-maximum.java
413.arithmetic-slices.java

打卡13:
208. Implement Trie (Prefix Tree)

8.23打卡：
two pointers:
167. Two Sum II - Input array is sorted
15. 3 Sum
16. 3Sum Closest
18. 4Sum
42. Trapping Rain Water
611. Valid Triangle Number
11. Container With Most Water
HashMap + two passes:
454. 4Sum II

8.23打卡：
Sort Letters by case
Valid Palindrome
Quick Sort / Quick Select
wiggle sort I / II
Sort Colors
Partition Array by Odd and Even
Parition Array
Kth Largest Number

有意思有意思。我也要加入。大佬们加油。

8/23
341.flatten-nested-list-iterator.java

打卡14:
131        Palindrome Partitioning       
132        Palindrome Partitioning II

8/25
212.word-search-ii.java
199.binary-tree-right-side-view.java
108.convert-sorted-array-to-binary-search-tree.java
48.rotate-image.java
113.path-sum-ii.java