Given two binary trees, write a function to check if they are equal or not. Two binary trees are considered equal if they are structurally identical and the nodes have the same value. 判断两棵树是否相同和之前的判断两棵树是否对称都是一样的原理,利用深度优先搜索DFS来递归.代码如下: 解法一: class Solu…

Given a binary tree, check whether it is a mirror of itself (ie, symmetric around its center). For example, this binary tree is symmetric: 1 / \ 2 2 / \ / \ 3 4 4 3 But the following is not: 1 / \ 2 2 \ \ 3 3 Note:Bonus points if you could solve it b…

LeetCode: Binary Tree Traversal 题目:树的先序和后序. 后序地址:https://oj.leetcode.com/problems/binary-tree-postorder-traversal/ 先序地址:https://oj.leetcode.com/problems/binary-tree-preorder-traversal/ 后序算法:利用栈的非递归算法.初始时,先从根节点一直往左走到底,并把相应的元素进栈:在循环里每次都取出栈顶元素,如果该栈顶元素的右…

LeetCode:Binary Tree Level Order Traversal 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,#,#,15,7}, 3 / \ 9 20 / \ 15 7 return its level ord…

paip.tree 生成目录树到txt后的折叠查看 作者Attilax ,  EMAIL:1466519819@qq.com  来源:attilax的专栏 地址:http://blog.csdn.net/attilax Tree命令自动生成目录树到txt   tree  d:\xxx /f   >tree.txt   导出txt文件... 但是,目录树要是可以结构化折叠查看走Ok兰... 测试累挂notepad++ ,editplus都不行...不能直接折叠查看... 替换tab符号为空格,在n…

[BZOJ2588]Count On a Tree(主席树) 题面 题目描述 给定一棵N个节点的树,每个点有一个权值,对于M个询问(u,v,k),你需要回答u xor lastans和v这两个节点间第K小的点权.其中lastans是上一个询问的答案,初始为0,即第一个询问的u是明文. 输入格式: 第一行两个整数N,M. 第二行有N个整数,其中第i个整数表示点i的权值. 后面N-1行每行两个整数(x,y),表示点x到点y有一条边. 最后M行每行两个整数(u,v,k),表示一组询问. 输出格式: M…

Dylans loves tree Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 131072/131072 K (Java/Others)Total Submission(s): 1444    Accepted Submission(s): 329 Problem Description Dylans is given a tree with N nodes. All nodes have a value A[i].Nodes…

BZOJ_2212_[Poi2011]Tree Rotations_线段树合并 Description Byteasar the gardener is growing a rare tree called Rotatus Informatikus. It has some interesting features: The tree consists of straight branches, bifurcations and leaves. The trunk stemming from t…

BZOJ_1803_Spoj1487 Query on a tree III_主席树 Description You are given a node-labeled rooted tree with n nodes. Define the query (x, k): Find the node whose label is k-th largest in the subtree of the node x. Assume no two nodes have the same labels. I…

平衡二叉树(Balanced Binary Tree 或 Height-Balanced Tree)又称AVL树 (a)和(b)都是排序二叉树,但是查找(b)的93节点就需要查找6次,查找(a)的93节点就需要查找3次,所以(b)的效率不高. 平衡二叉树(Balanced Binary Tree 或 Height-Balanced Tree)又称AVL树.它或者是一颗空树,或者是具有下列性质的二叉树:它的左子树和右子树的深度只差的绝对值不超过1.若将二叉树上节点的平衡因子BF(Balance F…