In a binary tree, the root node is at depth 0, and children of each depth knode are at depth k+1. Two nodes of a binary tree are cousins if they have the same depth, but have different parents. We are given the root of a binary tree with unique value…

Leetcode之深度优先搜索(DFS)专题-199. 二叉树的右视图(Binary Tree Right Side View) 深度优先搜索的解题详细介绍,点击 给定一棵二叉树,想象自己站在它的右侧,按照从顶部到底部的顺序,返回从右侧所能看到的节点值. 示例: 输入: [1,2,3,null,5,null,4] 输出: [1, 3, 4] 解释: 1 <--- / \ 2 3 <--- \ \ 5 4 <--- 分析:把每一行的值保存起来,最后再把每一行最后一个放进ans里. AC代码…

993. Cousins in Binary Tree In a binary tree, the root node is at depth 0, and children of each depth knode are at depth k+1. Two nodes of a binary tree are cousins if they have the same depth, but have different parents. We are given the root of a b…

problem 993. Cousins in Binary Tree 参考 1. Leetcode_easy_993. Cousins in Binary Tree; 完…

In a binary tree, the root node is at depth 0, and children of each depth k node are at depth k+1. Two nodes of a binary tree are cousins if they have the same depth, but have different parents. We are given the root of a binary tree with unique valu…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 DFS BFS 日期 题目地址:https://leetcode.com/problems/cousins-in-binary-tree/ 题目描述 In a binary tree, the root node is at depth 0, and children of each depth k node are at depth k+1. Tw…

Given a binary tree, find the leftmost value in the last row of the tree. Example 1: Input: 2 / \ 1 3 Output: 1 Example 2: Input: 1 / \ 2 3 / / \ 4 5 6 / 7 Output: 7 Note: You may assume the tree (i.e., the given root node) is not NULL. -------------…

题目要求 In a binary tree, the root node is at depth 0, and children of each depth k node are at depth k+1. Two nodes of a binary tree are cousins if they have the same depth, but have different parents. We are given the root of a binary tree with unique…

这是悦乐书的第374次更新,第401篇原创 01 看题和准备 今天介绍的是LeetCode算法题中Easy级别的第235题(顺位题号是993).在二叉树中,根节点在深度0处,并且每个深度为k的节点的子节点,他们深度为k + 1. 如果二元树的两个节点具有相同的深度但具有不同的父节点,则它们是堂兄弟. 我们给出了具有唯一值的二叉树root,以及树中两个不同节点的值x和y. 当且仅当对应于值x和y的节点是堂兄弟时,才返回true.例如: 输入:root = [1,2,3,4],x = 4,y = 3…

Return any binary tree that matches the given preorder and postorder traversals. Values in the traversals pre and post are distinct positive integers. Example 1: Input: pre = [1,2,4,5,3,6,7], post = [4,5,2,6,7,3,1] Output: [1,2,3,4,5,6,7] Note: 1 <=…