// 题目描述:一个项目被分成几个部分,每部分必须在连续的天数完成.也就是说,如果某部分需要3天才能完成,则必须花费连续的3天来完成它.对项目的这些部分工作中,有4种类型的约束:FAS, FAF, SAF和SAS.两部分工作之间存在一个FAS约束的含义是:第一部分工作必须在第二部分工作开始之后完成: Xa+Ta>=XbFAF约束的含义是:第一部分工作必须在第二部分工作完成之后完成: Xa+Ta>=Xb+TbSAF的含义是:第一部分工作必须在第二部分工作完成之后开始: Xa>=Xb+TbS…

THE MATRIX PROBLEM Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 8693    Accepted Submission(s): 2246 Problem Description You have been given a matrix CN*M, each element E of CN*M is positive…

Schedule Problem Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 1085    Accepted Submission(s): 448Special Judge Problem Description A project can be divided into several parts. Each part shoul…

差分约数: 求满足不等式条件的尽量小的值---->求最长路---->a-b>=c----> b->a (c) Schedule Problem Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 1503    Accepted Submission(s): 647 Special Judge Problem Descr…

// 差分约束系统// 火烧连营 // n个点 m条边 每天边约束i到j这些军营的人数 n个兵营都有容量// Si表示前i个军营的总数 那么 1.Si-S(i-1)<=C[i] 这里 建边(i-1,i) 权值为 C[i]// 2.S(i-1)-Si<=0 这里 建边(i,i-1) 权值为 0// 3.S(j)-S(i-1)>=k => S(i-1)-Sj<=-k 这里建边 (j,i-1) 权值为 -k// 题目求的事 Sn-S0的最小值 Sn-S0>=m 中符合条件的m…

差分约束系统讲解看这里:http://blog.csdn.net/xuezhongfenfei/article/details/8685313 模板题,不多说.要注意的一点是!!!对于带有within的语句,要建立两个不等式!!!x要在y开始的z分钟内开始的话,x<=y+z 并且 x>=y.别忘了. spfa判负权回路. In most recipes, certain tasks have to be done before others. For each task, if we are…

https://vjudge.net/problem/UVA-11478 给定一个有向图,每条边都有一个权值.每次你可以选择一个结点v和一个整数d,把所有以v为终点的边的权值减小d,把所有以v为起点的边的权值增加d,最后让所有边的权值的最小值大于零且尽量大. 该死书上翻译错了 >0不是非负 WA好几次因为这个 考虑每条边的约束,di表示i的halum量 w-dv+du>0 dv-du<w 但求解这个差分约束系统只是让这组不等式成立,最长路和最短路控制的都是单个d的最值而不是最小值最大 那…

Layout 题目链接: Rhttp://acm.hust.edu.cn/vjudge/contest/122685#problem/S Description Like everyone else, cows like to stand close to their friends when queuing for feed. FJ has N (2 <= N <= 1,000) cows numbered 1..N standing along a straight line waitin…

Problem  UVA - 11090 - Going in Cycle!! Time Limit: 3000 mSec Problem Description You are given a weighted directed graph with n vertices and m edges. Each cycle in the graph has a weight, which equals to sum of its edges. There are so many cycles in…

Problem  UVA - 11478 - Halum Time Limit: 3000 mSec Problem Description You are given a directed graph G(V,E) with a set of vertices and edges. Each edge (i,j) that connects some vertex i to vertex j has an integer cost associated with that edge. Defin…