POJ 1275 差分约束

一堆化不等式,,,,,,
懒得写了。。。
请看mars_ch的blog…..

戳戳戳戳戳

还是她给我找的错……….

//By SiriusRen
#include <queue>
#include <cstdio>
#include <cstring>
#include <algorithm>
using namespace std;
int first[25],next[666],v[666],w[666],tot,ans;
int n,cases,have[25],need[25],jy,inq[25],vis[25],dis[25];
void add(int x,int y,int z){w[tot]=z,v[tot]=y,next[tot]=first[x],first[x]=tot++;}
bool spfa(){
    queue<int>q;q.push(0);
    while(!q.empty()){
        int t=q.front();q.pop();
        vis[t]++,inq[t]=0;
        for(int i=first[t];~i;i=next[i])
            if(dis[v[i]]<dis[t]+w[i]){
                dis[v[i]]=dis[t]+w[i];
                if(!inq[v[i]])inq[v[i]]=1,q.push(v[i]);
                if(vis[v[i]]>24)return 0;
            }
    }
    if(dis[24]==ans)return 1;return 0;
}
int main(){
//  freopen("data.txt","r",stdin);
    scanf("%d",&cases);
    while(cases--){
        memset(have,0,sizeof(have));
        for(int i=1;i<=24;i++)scanf("%d",&need[i]);
        scanf("%d",&n);
        for(int i=1;i<=n;i++)scanf("%d",&jy),have[jy+1]++;
        for(ans=0;ans<=n;ans++){
            memset(dis,0xcf,sizeof(dis));memset(vis,0,sizeof(vis));
            tot=0,memset(first,-1,sizeof(first)),memset(inq,0,sizeof(inq));
            dis[0]=0;
            for(int i=1;i<=24;i++)add(i-1,i,0),add(i,i-1,-have[i]);
            for(int i=9;i<=24;i++)add(i-8,i,need[i]);
            add(0,24,ans);
            for(int i=1;i<=8;i++)add(i+16,i,need[i]-ans);
            if(spfa()){printf("%d
",ans);goto end;}
        }
        puts("No Solution");
        end:;
    }
}

这里写图片描述

原文地址:https://www.cnblogs.com/SiriusRen/p/6532321.html