1 /** 2  * Definition for binary tree 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 boolean hasPathSum(TreeNode root, int sum) {12         if(root==null) return false;13         if(root.val==sum&&root.left==null&&root.right==null)return true;14         if(root.left!=null)15         {16             if(hasPathSum(root.left,sum-root.val))17             return true;18         }19         if(root.right!=null)20         {21              if(hasPathSum(root.right,sum-root.val))22             return true;23         }    24         return false;25             26     }27 }