BJUT_bluecat的博客

解法：便利所有除了目标节点分支的节点，标记他们的爸爸和自己是左是右。然后从目标节点向外便利。/** * Definition for a binary tree node. * struct TreeNode { * int val; * TreeNode *left; * TreeNode *right; * TreeNode(int x) : val...

Given a 2d grid map of '1's (land) and '0's (water), count the number of islands. An island is surrounded by water and is formed by connecting adjacent lands horizontally or vertically. You may assume...

一个深度优先，最开始错误在想减少时间设置了visit数组，访问的不在访问，但实际是不对的。比如：[["0","0","0","1"],["1","1","0","1"],["1","1","1","1"],["0","1","1","1"],["0","1","1","1"]]后来老老实实做时间空间也都很好。Runtime: 20 ms, faster than 97.16% of...