Xiaomao要学coding

N sum Question 2 sum, 3 sum and 3 Sum closet 4 sum - > K sum

Reverse String Question 1 Reverse the string word by word (from leetcode) For example, Given s = "the sky is blue", return "blue is sky the". Clarification: What constitutes a word? A sequence

leetcode question Given an integer n, return the number of trailing zeroes in n!.Your solution should be in logarithmic time complexity. need to pay attention basic situation is N <= 0, no zero!

最开始觉得很简单dfs的题，但是再做的时候才发现第一次做的时候很多问题并没有想清楚想明白结合面经把这道题重新做一遍。 1 Path Sum from root to leaf leetcode原题 pathsumii Given a binary tree and a sum, find all root-to-leaf paths where each path's sum equ

leetcode上有四道题，主要是remove from linked list和array 都是two pointer解决，要注意终止条件，还有移动指针时条件