<pre name="code" class="html"> Cleaning Shifts Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 14425   Accepted: 3700 Description Farmer John is assigning some of his N (1 <= N <= 25,000) cows to do some cleani…

Cleaning Shifts Farmer John is assigning some of his N (1 <= N <= 25,000) cows to do some cleaning chores around the barn. He always wants to have one cow working on cleaning things up and has divided the day into T shifts (1 <= T <= 1,000,000…

Cleaning Shifts 题目连接: http://poj.org/problem?id=2376 Description Farmer John is assigning some of his N (1 <= N <= 25,000) cows to do some cleaning chores around the barn. He always wants to have one cow working on cleaning things up and has divided…

Cleaning Shifts Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 40751   Accepted: 9871 Description Farmer John is assigning some of his N (1 <= N <= 25,000) cows to do some cleaning chores around the barn. He always wants to have one co…

题意:给定1-m的区间,然后给定n个小区间,用最少的小区间去覆盖1-m的区间,覆盖不了,输出-1. 析:一看就知道是贪心算法的区间覆盖,主要贪心策略是把左端点排序,如果左端点大于1无解,然后, 忽略小于1的部分(如果有的话),再找最长的区间,然后把这个区间的右端点作为下次寻找的起点, 再找最大区间,直到覆盖到最后. 注意:首先要判断好能不能覆盖,不能覆盖就结束,有可能会提前结束,也要做好判断,我就在这WA了好几次, 悲剧...其他的就比较简单了,不用说了. 代码如下: #include <ios…

POJ 2376 Cleaning Shifts(轮班打扫) Time Limit: 1000MS   Memory Limit: 65536K [Description] [题目描述] Farmer John is assigning some of his N (1 <= N <= 25,000) cows to do some cleaning chores around the barn. He always wants to have one cow working on clean…

http://poj.org/problem?id=2376 Cleaning Shifts Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 12604   Accepted: 3263 Description Farmer John is assigning some of his N (1 <= N <= 25,000) cows to do some cleaning chores around the barn.…

POJ 2376 题意: 给出一给大区间和n各小区间,问最少可以用多少小区间覆盖整个大区间. 分析: 贪心法.设t为当前所有已确定区间的最右端,那我们可以每次都取所有可选的小区间(左端点<=t+1)中右端点最大的值,然后更新最右端点ans++.初始时t=0 注:所谓衔接不是[0,1][1,2]这样首尾相接,而是[0,1][2,3]即可,故为 t+1 #include<iostream> #include<algorithm> #include<string.h>…

题目地址: http://poj.org/problem?id=2376 题目内容: Cleaning Shifts Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 12226   Accepted: 3187 Description Farmer John is assigning some of his N (1 <= N <= 25,000) cows to do some cleaning chores arou…

http://poj.org/problem?id=2376 题目大意: 给你一些区间的起点和终点,让你用最小的区间覆盖一个大的区间. 思路: 贪心,按区间的起点找满足条件的并且终点尽量大的. 一开始排序还考虑了起点一样终点要大的,想了想没必要,因为只后都是直接扫描满足条件的.. 注意的是比如[4.5]下一次可以直接[6,10]这样...这一步坑了我好久... 后来一直WA,改了老半天...发现是大于等于少写了个等号,,,我去面壁...我要蹲墙角... #include<cstdio> #in…