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.

/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode(int x) { val = x; }
 * }
 */
//I missed it again.. Gosh I cannot forgive myself T^T
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;
    }
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