112.path-sum.py

#
# @lc app=leetcode id=112 lang=python3
#
# [112] Path Sum
#
# Definition for a binary tree node.
# class TreeNode:
#     def __init__(self, x):
#         self.val = x
#         self.left = None
#         self.right = None


class Solution:
    def hasPathSum(self, root: TreeNode, sum: int) -> bool:
        if not root:
            return False
        if root.left == None and root.right == None:
            return root.val == sum
        return self.hasPathSum(root.left, sum-root.val) or self.hasPathSum(root.right, sum-root.val)