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Course Schedule && Course Schedule || For Course Schedule Problem description: There are a total of n courses you have to take, labeled from 0 to n - 1. Some courses may have prerequisites,...

LintCode String, Function & Class 第一部分

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java 归并排序

Longest Palindrome Given a string which consists of lowercase or uppercase letters, find the length of the longest palindromes that can be built with those letters. This is case sensitive, for examp

Copy List with Random Pointer (复制有随机指针的链表) A linked list is given such that each node contains an additional random pointer which could point to any node in the list or null. Return a deep copy of t

Binary Tree and Recursion Ⅰ 这篇帖子简单讨论下二叉树这种数据结构以及一道二叉树算法题。 首先复习下二叉树的基本知识 二叉树特点 1、每个结点最多有两颗子树，结点的度最大为 2 2、左子树和右子树是有顺序的，次序不能颠倒 3、即使某结点只有一个子树，也要区分左右子树。 满二叉树和完全二叉树的定义 在一棵二叉树中，如果所有分支结点都存在左子树和右子树，并且叶子

Sort Algorithms 常见排序算法总结 本文将总结3种常见的排序算法，分别是冒泡排序法，选择排序法和快速排序法。 Bubble Sort：比较两个相邻的元素，将值大的元素交换至右端，持续此操作直至数组末端。经过这一趟比较，我们已经将数组中最大的元素放在了整个数组的最右端。然后需要对前面N-1个元素也利用同样的过程操作。由此可见：N个数字要排序完成，总共进行N-1趟排序，第i趟的排序次...

LeetCode Reverse Integer 先贴题目： Reverse digits of an integer. Example1: x = 123, return 321 Example2: x = -123, return -321 The input is assumed to be a 32-bit signed integer. Your function should...

LintCode Introduce Java 必做部分 9.4号美国劳动节放假一天，换个平台刷点算法题，先从基础的开始，由于这部分题目比较简单，我准备一个单元分两次写博客，一次必做题部分，一次选做题部分。今天带来的是第一单元必做题部分： 第一题 反转一个只有3位数的整数。 注意事项 你可以假设输入一定是一个只有三位数的整数，这个整数大于等于100，小于1000。 样例 123 反转...

LeetCode Merge Two Binary Trees 先看题目： Given two binary trees and imagine that when you put one of them to cover the other, some nodes of the two trees are overlapped while the others are not. You n...

LeetCode Judge Route Circle 先贴上题目： Initially, there is a Robot at position (0, 0). Given a sequence of its moves, judge if this robot makes a circle, which means it moves back to the original place....

LeetCode Encode and Decode TinyURL 先贴上题目： TinyURL is a URL shortening service where you enter a URL such as https://leetcode.com/problems/design-tinyurl and it returns a short URL such as http://tin...

LeetCode Hamming Distance 先贴题目 The Hamming distance between two integers is the number of positions at which the corresponding bits are different. Given two integers x and y, calculate the Hamming ...

LeetCode Two Sum 先贴上LeetCode第一题题目： Given an array of integers, return indices of the two numbers such that they add up to a specific target. You may assume that each input would have exactly one so...

LintCode Java Basic, Integer and Array