标签：spec elf binary int sum for leave ftl nod
Find the sum of all left leaves in a given binary tree.
Example:
3
/ 9 20
/ 15 7
There are two left leaves in the binary tree, with values 9 and 15 respectively. Return 24.
# Definition for a binary tree node. # class TreeNode(object): # def __init__(self, x): # self.val = x # self.left = None # self.right = None class Solution(object): def sumOfLeftLeaves(self, root): """ :type root: TreeNode :rtype: int """ if root is None: return 0 self.num = 0 self.helper(root,0) return self.num def helper(self, root, left): if root.left is None and root.right is None and left == 1: self.num += root.val if root.left: self.helper(root.left, 1) if root.right: self.helper(root.right, 0)
标签：spec elf binary int sum for leave ftl nod
原文地址：https://www.cnblogs.com/boluo007/p/12458109.html
