[leetcode]Minimum Depth of Binary Tree

Minimum Depth of Binary Tree

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.

 

跟[leetcode]Maximum Depth of Binary Tree 差不多。

递归，不多说。

public class Solution {
    public int minDepth(TreeNode root) {
        if(root == null) return 0;
        if(root.left == null && root.right == null) return 1;
        int left = Integer.MAX_VALUE,right = Integer.MAX_VALUE;
        if(root.left != null) left = minDepth(root.left);
        if(root.right != null) right =  minDepth(root.right);
        return left > right ? right + 1 : left +1;
    }
}