Leetcode 111. Minimum Depth of Binary Tree 二叉树最小深度

1 解题思想

找出一个二叉树的最矮的（深度最小）的那个值。

方法很简单，直接遍历，Easy难度

2 原题

Given a binary tree, find its minimum depth.
The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node.

3 AC解

/** * Definition for a binary tree node. * public class TreeNode { *     int val; *     TreeNode left; *     TreeNode right; *     TreeNode(int x) { val = x; } * } */ /**  * 直接遍历就好，并且如果当前搜索的长度大于当前最小值，就不往下走了  * */public class Solution {    int min;    public void dfs(int deep,TreeNode root){        if(deep>=min || root==null)            return ;        deep++;        if(root.left==null && root.right==null){            min=Math.min(deep,min);        }        dfs(deep,root.left);        dfs(deep,root.right);    }    public int minDepth(TreeNode root) {        if(root==null)            return 0;        min=Integer.MAX_VALUE;        dfs(0,root);        return min;    }}