三个月算法进阶--day64

class Solution:
    def pathSum(self, root: TreeNode, sum: int) -> List[List[int]]:
        ans, path = [], []
        def cur(node, target):
            if not node:
                return
            path.append(node.val)
            target -= node.val
            if target == 0 and not node.left and not node.right:
                ans.append(list(path))
            cur(node.left, target)
            cur(node.right, target)
            path.pop()
        cur(root, sum)
        return ans