Sept. 13, 2015 Spent more than a few hours to work on the leetcode problem, and my favorite blogs about this problems: 1. http://siddontang.gitbooks.io/leetcode-solution/content/tree/construct_binary_tree.html 2.http://blog.csdn.net/linhuanmars/artic…

Given inorder and postorder traversal of a tree, construct the binary tree. Note: You may assume that duplicates do not exist in the tree. 这道题要求从中序和后序遍历的结果来重建原二叉树,我们知道中序的遍历顺序是左-根-右,后序的顺序是左-右-根,对于这种树的重建一般都是采用递归来做,可参见我之前的一篇博客Convert Sorted Array to Bin…

Given preorder and inorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree. 这道题要求用先序和中序遍历来建立二叉树,跟之前那道Construct Binary Tree from Inorder and Postorder Traversal 由中序和后序遍历建立二叉树原理基本相同,针对这道题,由于先…

Given inorder and postorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree. class Solution { public: TreeNode *buildTree(vector<int>& inorder, int in_left,int in_right, vector<int&…

Problem Link: https://oj.leetcode.com/problems/construct-binary-tree-from-preorder-and-inorder-traversal/ The basic idea is same to that for Construct Binary Tree from Inorder and Postorder Traversal. We solve it using a recursive function. First, we…

Given inorder and postorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree. Subscribe to see which companies asked this question /** * Definition for a binary tree node. * struct TreeNode…

Construct Binary Tree from Inorder and Postorder Traversal Given inorder and postorder traversal of a tree, construct the binary tree. 根据后序遍历和中序遍历构建一棵二叉树 /** * Definition for a binary tree node. * struct TreeNode { * int val; * TreeNode *left; * Tree…

Construct Binary Tree from Preorder and Inorder Traversal Given preorder and inorder traversal of a tree, construct the binary tree. 分析: 根据前序遍历和中序遍历构造一棵树,递归求解即可 /** * Definition for a binary tree node. * struct TreeNode { * int val; * TreeNode *left;…

Construct minimum number by reordering a given non-negative integer array. Arrange them such that they form the minimum number. Notice The result may be very large, so you need to return a string instead of an integer. Have you met this question in a…

Given preorder and inorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree. 此题目有两种解决思路: 1)递归解决(比较好想)按照手动模拟的思路即可 2)非递归解决,用stack模拟递归 class Solution { public: TreeNode *buildTree(vector<int>&…

Given inorder and level-order traversals of a Binary Tree, construct the Binary Tree. Following is an example to illustrate the problem. BinaryTree Input: Two arrays that represent Inorder and level order traversals of a Binary Treein[]    = {4, 8, 1…

题目: Given preorder and inorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree. 解题思路分析: 前序遍历首先遍历根节点,然后依次遍历左右子树 中序遍历首先遍历左子树,然后遍历根结点,最后遍历右子树 根据二者的特点,前序遍历的首节点就是根结点,然后在中序序列中找出该结点位置(index),则该结点之…

Given preorder and inorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree. Solution: Just do it recursively. TreeNode *build(vector<int> &preorder, int pstart, int pend, vector<int…

Problem Link: https://oj.leetcode.com/problems/construct-binary-tree-from-inorder-and-postorder-traversal/ This problem can be easily solved using recursive method. By given the inorder and postorder lists of the tree, i.e. inorder[1..n] and postorde…

Construct Binary Tree from Inorder and Postorder Traversal OJ: https://oj.leetcode.com/problems/construct-binary-tree-from-inorder-and-postorder-traversal/ Given inorder and postorder traversal of a tree, construct the binary tree. Note: You may assu…

boost中的IPC进程间通信非常好用,可以直接在共享内存上创建对象,相当于new分配器,实测发现它的分配算法还是有点耗时.第一个测试代码仅仅分配一次,然后频繁的复制,每秒钟可以复制4200次左右. // HelloBoostIPC.cpp : Defines the entry point for the console application. // #include "stdafx.h" #include <boost/interprocess/managed_shared…

LeetCode:Construct Binary Tree from Inorder and Postorder Traversal Given inorder and postorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree.                                            …

ThinkPHP中initialize()和construct()这两个函数都可以理解为构造函数,前面一个是tp框架独有的,后面的是php构造函数,那么这两个有什么不同呢? 在网上搜索,很多答案是两者是一样的,ThinkPHP中initialize相当于php的construct,这么说是错误的,如果这样,tp为什么不用construct,而要自己弄一个ThinkPHP版的initialize构造函数呢? 自己试一下就知道两者的不同了. a.php class a{ function __con…

题目链接:Construct a Matrix 题意:构造一个矩阵,要求矩阵的每行每列的和都不相同.矩阵的边长是前n项斐波那契的和. 思路:由sn = 2*(fn-1)+(fn-2)-1,只要知道第n-1和第n-2项即可,n的范围是10^9,可由矩阵快速幂求出第n项.然后,构造矩阵,上三角为1,下三角全为-1,对角线1和0交替.[真是个天才...!!!]矩阵快速幂求第n项时,构造的矩阵是a[0][0] = f2, a[1][0] = f1, a[0][1] = 1, a[1][1] = 0...…

Given inorder and postorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree. 和上一道题基本一样 根据中序和后序遍历确定一个棵树. /** * Definition for a binary tree node. * public class TreeNode { * int val; * TreeN…

Given preorder and inorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree. 给出前序遍历和中序遍历,然后求这棵树. 很有规律.递归就可以实现. /** * Definition for a binary tree node. * public class TreeNode { * int val; *…

Given inorder and postorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree. ======== 利用:中序+后序遍历 ==== code: /** * Definition for a binary tree node. * struct TreeNode { * int val; * TreeNod…

Given preorder and inorder traversal of a tree, construct the binary tree. ============== 基本功: 利用前序和中序构建二叉树 , === code /** * Definition for a binary tree node. * struct TreeNode { * int val; * TreeNode *left; * TreeNode *right; * TreeNode(int x) : va…

题目: Given inorder and postorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree. 代码: /** * Definition for a binary tree node. * struct TreeNode { * int val; * TreeNode *left; * TreeNode *ri…

题目: Given preorder and inorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree. 代码: /** * Definition for a binary tree node. * struct TreeNode { * int val; * TreeNode *left; * TreeNode *rig…

一.前言 上一篇,我先完成了对内存配置器的实现.然而后面在内存上的算法还依赖于两个全局函数,construct()和destroy(),前者负责在指定的内存上调用对象的构造函数,在内存上构造出对象.后者则是相反,在指定内存上调用对象的析构函数,销毁对象.(注意:这两个函数不涉及对象内存的分配和释放,对象构造在指定的已分配好的内存上,析构也只是销毁对象,对于对象占用的那块内存,没有释放,如需释放,还需自己去free). 二.全局construct()函数简介 construct(),主要功能前面已…

<?php class A { //特别注意,这里的下划线为两个 function __construct() { echo "I am the constructor of A.<br>\n"; } function B() { echo "I am a regular function named B in class A.<br>\n"; echo "I am not a constructor in A.<br&…

Given preorder and inorder traversal of a tree, construct the binary tree. 题目大意:给定一个二叉树的前序和中序序列,构建出这个二叉树. 解题思路:跟中序和后序一样,在先序中取出根节点,然后在中序中找到根节点,划分左右子树,递归构建这棵树,退出条件就是左右子树长度为1,则返回这个节点,长度为0则返回null. Talk is cheap: public TreeNode buildTree(int[] preorder,…

Given inorder and postorder traversal of a tree, construct the binary tree. 题目大意:给定一个二叉树的中序和后续序列,构建出这个二叉树. 解题思路:首先后序序列的最后一个是根节点,然后在中序序列中找到这个节点,中序序列中这个节点左边的是根节点的左子树,右边的是右子树,由此递归构建出完整的树. Talk is cheap: public TreeNode buildTree(int[] inorder, int[] pos…

Given inorder and postorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree. 这个题目是给你一棵树的中序遍历和后序遍历,让你将这棵树表示出来.其中可以假设在树中没有重复的元素. 当做完这个题之后,建议去做做第105题,跟这道题类似. 分析:这个解法的基本思想是:我们有两个数组,分别是IN和POST.后…