[第五期活动] 在职刷题打卡，目标工作日一天2题，周末一天5题

# Day 14/14
- 921 minimum add to make parentheses valid
-1256 encode number
-1257 smallest common region
- 935 knight dialer
-1261 find elements in a contaminated binary tree

11.16,2019 [Day1]
20: Valid Parenthesis
23: Merge K Sorted Lists
45: Jump Game II
49: Group Anagram
138: Copy List with Random Pointer

[19/11/16][Day 2] 3题

Topic: Array
26. Remove Element
27. Remove Duplicates from Sorted Array
80. Remove Duplicates from Sorted Array II

今天刷题开始总结模版了，感觉相似的题在一起刷效率会更高。每天要把题量提上来，加油！

[Day 15][Total Day 27] 2019/11/16，Topic：Stack（Lintcode）
- 629. Minimum Spanning Tree
- 12. Min Stack
- 575. Decode String

11/15 【2题】
311. Sparse Matrix Multiplication
12. Integer to Roman

# day 13/13
147. Insertion Sort List

[19/11/15][Day 1]

273. Integer to English Words
      - 这个题目在哪里加空格还挺tricky的，最后提交的时候思考了一下
      - corner case需要仔细思考，细节比较多

加油！坚持！

day11
DP day & more ez ones
926. Flip String to Monotone Increasing
801. Minimum Swaps To Make Sequences Increasing
845. Longest Mountain in Array
1137. N-th Tribonacci Number

[Day 14][Total Day 26] 2019/11/15，Topic：UnionFind & Trie（Lintcode）
- 634. Word Squares
- 132. Word Search II

#Day4
767        Reorganize String        Heap        Maxheap
23        Merge k Sorted Lists        Heap        Minheap