分治算法简介——归并排序
归并排序应用分治算法，具有O(nlogn)的时间复杂度，其工作流程可以概述为： 将长度为n的无序序列分割成n个子序列，每个序列包含1个元素； 重复将子序列相互合并称为有序序列，直到只剩下1个序列，即为排序后的序列。 一个例程如下所示： void merge(int array[], int tmpArray[], int lPos, int rPos, int rEnd) { int i,…
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Bellman-Ford算法简介
Bellman-Ford算法用于计算有向图中的单源最短路径。对于有V个顶点和E条边的图，Bellman-Ford的时间复杂度为O(V·E)，效率低于Dijkstra算法。Bellman-Ford可以用于有负权边的情况，且能判断负权环，十分灵活。 Wiki上给出的Bellman-Ford算法的伪代码如下所示： function BellmanFord(list vertices, list …
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URAL 1008. Image Encoding
1. 题目 http://acm.timus.ru/problem.aspx?space=1&num=1008 1008. Image Encoding Time limit: 2.0 second Memory limit: 64 MB There are several ways to encode an image. In this problem we will consider …
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URAL 1072. Routing
1. 题目 http://acm.timus.ru/problem.aspx?space=1&num=1072 1072. Routing Time limit: 1.0 second Memory limit: 64 MB There is a TCP/IP net of several computers. It means that: Each computer has one or…
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POJ 3414. Pots
1. 题目 http://poj.org/problem?id=3414 Pots Time Limit: 1000MS Memory Limit: 65536K Total Submissions: 12107 Accepted: 5110 Special Judge Description You are given two pots, having the volume of A and B…
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URAL 1080. Map Coloring
1. 题目 http://acm.timus.ru/problem.aspx?space=1&num=1080 1080. Map Coloring Time limit: 1.0 second Memory limit: 64 MB We consider a geographical map with N countries numbered from 1 to N (0 < N…
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URAL 1033. Labyrinth
1. 题目 http://acm.timus.ru/problem.aspx?space=1&num=1033 1033. Labyrinth Time limit: 1.0 second Memory limit: 64 MB Administration of the labyrinth has decided to start a new season with new wallpa…
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URAL 1837. Isenbaev’s Number
1. 题目 http://acm.timus.ru/problem.aspx?space=1&num=1837 1837. Isenbaev’s Number Time limit: 0.5 second Memory limit: 64 MB Vladislav Isenbaev is a two-time champion of Ural, vice champion o…
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URAL 1263. Elections
1. 题目 http://acm.timus.ru/problem.aspx?space=1&num=1643 1263. Elections Time limit: 1.0 second Memory limit: 64 MB The next in turn elections are to come soon. All the fences are postered with lea…
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