链接:LeetCode111
过程:略
思路:dfs,看题解觉得bfs较好
代码:
/**
* Definition for a binary tree node.
* public class TreeNode {
* int val;
* TreeNode left;
* TreeNode right;
* TreeNode(int x) { val = x; }
* }
*/
class Solution {
public int minDepth(TreeNode root) {
if(root==null)return 0;
if(root.left==null&&root.right==null)return 1;
if(root.left==null){
return minDepth(root.right)+1;
}
if(root.right==null){
return minDepth(root.left)+1;
}
return Math.min(minDepth(root.left),minDepth(root.right))+1;
}
}