[0]) for element in elements[1:]: insert(Tree, element) return Tree class Solution(object): def postorderTraversal(self, root): if not root: return [] res = [] stack = [[root,0]] while stack: node = stack[-1] stack.pop() if node[1]== 0 : current = node[0] stack....
# Python program to introduce Binary Tree# A class that represents an individual node in a# Binary TreeclassNode:def__init__(self,key):self.left=Noneself.right=Noneself.val=key# create rootroot=Node(1)''' following is the tree after above statement1/ \None None'''root.left=Node(2);...
链接:https://leetcode-cn.com/problems/binary-tree-inorder-traversal python # 0094.二叉树中序遍历 # 递归 & 迭代 class Solution: def inOrderRecur(self,head: TreeNode) -> int: """ 递归遍历,LNR, 左根右 :param head: :return: """ def traversal(head): # 递归终止条件 ifhead== None: ...
Binary Tree Level Order Traversal二叉树的层次遍历【Medium】【Python】【BFS】 Problem LeetCode Given a binary tree, return the level order traversal of its nodes’ values. (ie, from left to right, level by level). For example: Given binary tree [3,9,20,null,null,15,7], 3 / \ 9 20...
LeetCode 0102. Binary Tree Level Order Traversal二叉树的层次遍历【Medium】【Python】【BFS】 Problem LeetCode Given a binary tree, return thelevel ordertraversal of its nodes' values. (ie, from left to right, level by level). For example: ...
[Leetcode][python]Binary Tree Zigzag Level Order Traversal,题目大意按之字形遍历二叉树(一正一反)解题思路来自:链接解题思路:这道题和上一题层序遍历那道题差不多,区别只是在于奇数层的节点要翻转过来存入数组。代码:代码BFSclassSolution(object):defzigzagLeve
Write a Python program to find the kth smallest element in a given binary search tree.Sample Solution: Python Code:class TreeNode(object): def __init__(self, x): self.val = x self.left = None self.right = None def kth_smallest(root, k): stack = [] while root or...
[Leetcode][python]Binary Tree Preorder Traversal/二叉树的前序遍历,题目大意二叉树前序遍历挑战:迭代解题解题思路递归简单
Python3 C# 给定二叉搜索树, 编写一个函数, 该函数以以下三个作为参数: 1)树的根 2)旧键值 3)新的关键值 该功能应将旧键值更改为新键值。该函数可以假定二叉搜索树中始终存在旧键值。 例子: Input: Root of below tree 50 / \ 30 70 / \ / \ ...
解题思路:由于编程语言为python,所以其实在Binary Tree Level Order Traversal这道题(http://www.cnblogs.com/zuoyuan/p/3722004.html)的基础上加一句res.reverse()就可以了。 代码: # Definition for a binary tree node # class TreeNode: # def __init__(self, x): # self.val = x # self.left =...