111. Minimum Depth of Binary Tree java solutions

 1 /**
 2  * Definition for a binary tree node.
 3  * public class TreeNode {
 4  *     int val;
 5  *     TreeNode left;
 6  *     TreeNode right;
 7  *     TreeNode(int x) { val = x; }
 8  * }
 9  */
10 public class Solution {
11     public int minDepth(TreeNode root) {
12         if(root == null) return 0;
13         if(root.left == null) return 1 + minDepth(root.right);
14         if(root.right == null) return 1 + minDepth(root.left);
15         return Math.min(minDepth(root.left),minDepth(root.right)) + 1;
16     }
17 }