【leetCode】Path Sum II python实现

Path Sum II

原题链接

Path Sum II

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实现原理解析

该题使用深度搜索实现即可

python代码实现

import copy# Definition for a binary tree node.# class TreeNode(object):#     def __init__(self, x):#         self.val = x#         self.left = None#         self.right = Noneclass Solution(object):    def __init__(self):        self.path = []        self.result = []    def pathSum(self, root, sum):        """        :type root: TreeNode        :type sum: int        :rtype: List[List[int]]        """        self.dfs(root, sum)        return self.result    def dfs(self, root, res):        if root is None:            return        elif root.left is None and root.right is None:            if sum(self.path) + root.val == res:                self.path.append(root.val)                path1 = copy.deepcopy(self.path)                self.result.append(path1)                self.path.pop()        else:            self.path.append(root.val)            self.pathSum(root.left, res)            self.pathSum(root.right, res)            self.path.pop()