# class TreeNode:
# def __init__(self, x):
# self.val = x
# self.left = None
# self.right = None
#
#
# @param root TreeNode类
# @param sum int整型
# @return bool布尔型
#
class Solution:
def hasPathSum(self , root , sum ):
# write code here
if not root:
return False
if sum==root.val and not root.left and not root.right:
return True
return self.hasPathSum(root.left, sum-root.val) or self.hasPathSum(root.right, sum-root.val)