路径总和二叉树

class Solution {
    public boolean hasPathSum(TreeNode root, int targetSum) {
      if(root==null)return false;
      if(root.left==null && root.right==null)return root.val==targetSum;
      return hasPathSum(root.left,targetSum-root.val) || hasPathSum(root.right,targetSum-root.val);
    }
}