112. 路径总和

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# Definition for a binary tree node.
# class TreeNode:
#     def __init__(self, val=0, left=None, right=None):
#         self.val = val
#         self.left = left
#         self.right = right
class Solution:
    def __init__(self):
        self.first_vale = [] 
    def hasPathSum(self, root: Optional[TreeNode], targetSum: int) -> bool:
        if root==None: return False
        self.first_vale.append(root.val)
        print(targetSum)
        # 基线条件
        if root.left==None and root.right==None and targetSum==self.first_vale[0]:
            print("--- ")
            return True 
        if root.left==None and root.right==None and targetSum!=self.first_vale[0]:
            return False 
        if root.left:
            targetSum -= root.left.val
            if self.hasPathSum(root.left,targetSum):
                return True 
            targetSum += root.left.val
        if root.right:
            targetSum -= root.right.val
            if self.hasPathSum(root.right,targetSum):
                return True 
            targetSum += root.right.val
        return False