hdoj1529

Problem : 1529 ( Cashier Employment )     Judge Status : Accepted
RunId : 2664468    Language : G++    Author : huwenbiao
Code Render Status : Rendered By HDOJ G++ Code Render Version 0.01 Beta

/***************************************************************\
 *Author:Hu Wenbiao
 *Created Time: Thu 22 Jul 2010 06:10:59 PM CST
 *File Name: main.cpp
 *Description:差分约束系统
\***************************************************************/
//*========================*Head File*========================*\\

#include<iostream>
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
/*----------------------*Global Variable*----------------------*/
struct E{
    int s,e,len;//起点，终点，长度
}edges[100];
int R[26],num[26],ans,T,N,cnt,dist[26],t;
//*=======================*Main Program*=======================*//
using namespace std;

bool bellman_ford(){
    int _cnt=cnt;
    int s,e,len;
    edges[_cnt].s=0;
    edges[_cnt].e=24;
    edges[_cnt].len=ans;
    _cnt++;
    for(int i=1;i<=8;i++){//S[i]-S[i+16]>=R[i] (1<=i<=8)
        edges[_cnt].s=i+16;
        edges[_cnt].e=i;
        edges[_cnt].len=R[i]-ans;
        _cnt++;
    }
    memset(dist,0,sizeof(dist));
    dist[24]=ans;
    for(int i=0;i<72;i++){//这儿我不知道为什么24不行，有大牛知道的话麻烦告诉一下
        bool flag=true;
        for(int j=0;j<_cnt;j++){
            s=edges[j].s,e=edges[j].e,len=edges[j].len;
            if(dist[e]<dist[s]+len){//求最长路径
                flag=false;
                dist[e]=dist[s]+len;
            }
        }
        if(flag)break;
    }
    return ans==dist[24];
}
int main(){
    //freopen("input","r",stdin);
    scanf("%d",&T);
    while(T--){
        memset(num,0,sizeof(num));
        for(int i=1;i<=24;i++)//时间全加1
          scanf("%d",R+i);
        scanf("%d",&N);
        for(int i=0;i<N;i++){
            scanf("%d",&t);
            num[t+1]++;
        }
        cnt=0;//标记边数
        for(int i=1;i<=24;i++){//S[i]-S[i-1]>=0 (1<=i<=24)
            edges[cnt].s=i-1;
            edges[cnt].e=i;
            edges[cnt].len=0;
            cnt++;
        }
        for(int i=1;i<=24;i++){//S[i]-S[i-1]<=num[i] (1<=i<=24)
            edges[cnt].s=i;
            edges[cnt].e=i-1;
            edges[cnt].len=-num[i];
            cnt++;
        }
        for(int i=1;i<24;i++){//S[i]-S[0]>=0 (1<=i<=23,24在bellman_ford()函数里)
            edges[cnt].s=0;
            edges[cnt].e=i;
            edges[cnt].len=0;
            cnt++;
        }
        for(int i=9;i<=24;i++){//S[i]-S[i-8]>=R[i] (9<=i<=24,
                               //1~8涉及到S[24],在bellman_ford()函数里)
            edges[cnt].s=i-8;
            edges[cnt].e=i;
            edges[cnt].len=R[i];
            cnt++;
        }
        ans=N;
        if(!bellman_ford())
          printf("No Solution\n");
        else{
            int s=0,t=N;
            ans=(t+s)/2;
            while(s<t){//二分
                if(bellman_ford()){
                    t=ans;
                    ans=(s+t)/2;
                }
                else{
                    s=ans+1;
                    ans=(s+t)/2;
                }
            }
            printf("%d\n",ans);
        }
    }
}