hdu 4862 Jump 上下界费用流

#include <stdio.h>
#include <iostream>
#include <string.h>
using namespace std;
const int N=800;
const int MAXE=200000;
const int inf=1<<30;
int head[N],s,t,cnt,ans,ss,tt;
int d[N],pre[N];
bool vis[N];
int q[MAXE];
struct Edge
{
    int u,v,c,w,next;
}edge[MAXE];

void addedge(int u,int v,int w,int c)
{
    edge[cnt].u=u;
    edge[cnt].v=v;
    edge[cnt].w=w;
    edge[cnt].c=c;
    edge[cnt].next=head[u];
    head[u]=cnt++;
    edge[cnt].v=u;
    edge[cnt].u=v;
    edge[cnt].w=-w;
    edge[cnt].c=0;
    edge[cnt].next=head[v];
    head[v]=cnt++;
}

int SPFA()
{
    int l,r;
    memset(pre,-1,sizeof(pre));
    memset(vis,0,sizeof(vis));
    for(int i=0;i<=t;i++) d[i]=inf;
    d[s]=0;
    l=0;r=0;
    q[r++]=s;
    vis[s]=1;
    while(l<r)
    {
        int u=q[l++];
        vis[u]=0;
        for(int j=head[u];j!=-1;j=edge[j].next)
        {
            int v=edge[j].v;
            if(edge[j].c>0&&d[u]+edge[j].w<d[v])
            {
                d[v]=d[u]+edge[j].w;
                pre[v]=j;
                if(!vis[v])
                {
                    vis[v]=1;
                    q[r++]=v;
                }
            }
        }
    }
    if(d[t]==inf)
        return 0;
    return 1;
}

int MCMF()
{
    int flow=0;
    while(SPFA())
    {
        int u=t;
        int mini=inf;
        while(u!=s)
        {
            if(edge[pre[u]].c<mini)
                mini=edge[pre[u]].c;
                u=edge[pre[u]].u;
        }
        flow+=mini;
        u=t;
        ans+=d[t]*mini;
        while(u!=s)
        {
            edge[pre[u]].c-=mini;
            edge[pre[u]^1].c+=mini;
            u=edge[pre[u]].u;
        }
    }
    return flow;
}

int main()
{
    int cas,n,m,k;
    scanf("%d",&cas);
    int val[20][20],id[20][20];
    int now=0;
    char str[20];
    while(cas--)
    {
        now++;
        int i,j,l;
        scanf("%d%d%d",&n,&m,&k);
        for(i=1;i<=n;i++)
        {
            scanf("%s",str+1);
            for(j=1;j<=m;j++)
                val[i][j]=str[j]-‘0‘;
        }
        s=0;ss=m*n*2+1;
        t=m*n*2+4;tt=m*n*2+3;
        for(i=0;i<=t;i++) head[i]=-1;
        cnt=0;
        for(i=1;i<=n;i++)
            for(j=1;j<=m;j++)
                id[i][j]=++cnt;
        cnt=0;
        addedge(tt,ss,0,inf);
        addedge(ss,ss+1,0,k);
        for(i=1;i<=n;i++)
            for(j=1;j<=m;j++)
            {
                addedge(s,id[i][j],0,1);
                addedge(id[i][j]+m*n,t,0,1);
                addedge(id[i][j],tt,0,1);
                addedge(ss+1,id[i][j]+m*n,0,1);
                for(l=j+1;l<=m;l++)
                {
                    if(val[i][j]==val[i][l]) addedge(id[i][j],id[i][l]+m*n,l-j-1-val[i][j],1);
                    else addedge(id[i][j],id[i][l]+m*n,l-j-1,1);
                }
                for(l=i+1;l<=n;l++)
                {
                    if(val[l][j]==val[i][j]) addedge(id[i][j],id[l][j]+m*n,l-i-1-val[i][j],1);
                    else addedge(id[i][j],id[l][j]+m*n,l-i-1,1);
                }
            }
            ans=0;
            int flow=MCMF();
            if(flow==m*n) printf("Case %d : %d\n",now,-ans);
            else printf("Case %d : -1\n",now);
    }
    return 0;
}