tyvj P1135 - 植物大战僵尸 最大权闭合图

#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<vector>
using namespace std;
#define MAXN 42
#define MAXM 63
#define MAXB MAXN*MAXM*4
#define MAXV MAXB*4
#define MAXE MAXB*1000
#define INF 0x3f3f3f3f
vector<int> att[MAXB];
int score[MAXB];
struct Edge
{
        int np,val;
        Edge *next,*neg;
}E[MAXE],*V[MAXV];
int tope=-1;
int sour=0,sink=1;
void addedge(int x,int y,int z)
{
        //cout<<"ADD:"<<x<<" "<<y<<" "<<z<<endl;
        E[++tope].np=y;
        E[tope].val=z;
        E[tope].next=V[x];
        V[x]=&E[tope];

        E[++tope].np=x;
        E[tope].val=0;
        E[tope].next=V[y];
        V[y]=&E[tope];

        E[tope].neg=&E[tope-1];
        E[tope-1].neg=&E[tope];
}
int lev[MAXV];
int dfs(int now,int maxf)
{
        int ret=0,t;
        Edge *ne;
        if(now==sink)return maxf;
        for (ne=V[now];ne;ne=ne->next)
        {
                if (lev[ne->np]!=lev[now]+1 || !ne->val)continue;
                t=dfs(ne->np,min(maxf,ne->val));
                ne->val-=t;
                ne->neg->val+=t;
                ret+=t;
                maxf-=t;
        }
        if (!ret) lev[now]=-1;
        return ret;
}
int q[MAXV];
int vis[MAXV],bfstime=0;
bool bfs()
{
        int head=-1,tail=0;
        int now;
        Edge *ne;
        q[0]=sour;
        vis[sour]=++bfstime;
        while (head<tail)
        {
                now=q[++head];
                for (ne=V[now];ne;ne=ne->next)
                {
                        if (!ne->val || vis[ne->np]==bfstime)continue;
                        vis[ne->np]=bfstime;
                        lev[ne->np]=lev[now]+1;
                        q[++tail]=ne->np;
                }
        }
        return vis[sink]==bfstime;
}
int dinic()
{
        int ret=0;
        while (bfs())
        {
                ret+=dfs(sour,INF);
        }
        return ret;
}
int low[MAXB],dfn[MAXB];
int dfstime=0;
int stack[MAXB],tops=-1;
bool ok[MAXB];
void tarjan(int now)
{
        int i,j;
        low[now]=dfn[now]=++dfstime;
        stack[++tops]=now;
        for (i=0;i<att[now].size();i++)
        {
                if (vis[att[now][i]])continue;
                if (!dfn[att[now][i]])
                {
                        tarjan(att[now][i]);
                        low[now]=min(low[now],low[att[now][i]]);
                }else
                {
                        low[now]=min(low[now],dfn[att[now][i]]);
                }
        }
        if (low[now]==dfn[now])
        {
                if (stack[tops]==now)
                {
                        tops--;
                }else
                {
                        while (stack[tops]!=now)
                        {
                                ok[stack[tops--]]=false;
                        }
                        ok[stack[tops--]]=false;
                }
        }
        vis[now]=1;
}
int main()
{
        freopen("input.txt","r",stdin);
        //freopen("output.txt","w",stdout);
        int i,j,k,x,y,z,n,m;
        scanf("%d%d",&n,&m);
        for (i=0;i<n;i++)
        {
                for (j=0;j<m;j++)
                {
                        scanf("%d%d",&score[i*m+j],&x);
                        for (k=0;k<x;k++)
                        {
                                scanf("%d%d",&y,&z);
                                if (y==i && z<j)continue;
                                att[i*m+j].push_back(y*m+z);
                        }
                }
        }
        for (i=0;i<n;i++)
        {
                for (j=0;j<m;j++)
                {
                        for (k=0;k<j;k++)
                        {
                                att[i*m+j].push_back(i*m+k);
                        }
                }
        }
        int l=n*m;
        memset(vis,0,sizeof(vis));
        memset(ok,1,sizeof(ok));
        for (i=0;i<l;i++)
        {
                if (!dfn[i])
                        tarjan(i);
        }
        bool flag;
        for (i=0;i<l;i++)
        {
                for (j=0;j<att[i].size();j++)
                {
                        if (!ok[att[i][j]])continue;
                        addedge(2+att[i][j],2+i,INF);
                }
        }
        int ans=0;
        for (i=0;i<n;i++)
        {
                for (j=m-1;j>=0;j--)
                {
                        if (!ok[i*m+j])break;
                        if (score[i*m+j]>=0)
                        {
                                addedge(sour,2+i*m+j,score[i*m+j]);
                                ans+=score[i*m+j];
                        }else
                        {
                                addedge(2+i*m+j,sink,-score[i*m+j]);
                        }
                }
        }
        ans-=dinic();
        printf("%d\n",ans);
        return 0;
}