bzoj 3504: [Cqoi2014]危桥

 #include<cstdio>
 #include<iostream>
 #include<cstring>
 #define M 100009
 #define inf 2139062143
 using namespace std;
 int n,a1,a2,an,b1,b2,bn,tot,cnt=,T,ans,head[M],d[M],q[*M],next[*M],u[*M],v[*M];
 char ch[][];
 bool bfs()
 {
     memset(d,,sizeof(int)*(T+));
     int h=,t=;
     q[]=;
     d[]=;
     for(;h<t;)
       {
         h++;
         int p=q[h];
         for(int i=head[p];i;i=next[i])
           if(!d[u[i]]&&v[i])
             {
                 d[u[i]]=d[p]+;
                 if(d[T])
                   return ;
                 t++;
                 q[t]=u[i];
             }
       }
     return ;
 }
 int dinic(int s,int f)
 {
     if(s==T)
       return f;
     int rest=f;
     for(int i=head[s];i&&rest;i=next[i])
       if(v[i]&&d[u[i]]==d[s]+)
         {
             int now=dinic(u[i],min(rest,v[i]));
             if(!now)
               d[u[i]]=;
             v[i]-=now;
             v[i^]+=now;
             rest-=now;
         }
     return f-rest;
 }
 void jia1(int a1,int a2,int a3)
 {
     cnt++;
     next[cnt]=head[a1];
     head[a1]=cnt;
     u[cnt]=a2;
     v[cnt]=a3;
     return;
 }
 void jia(int a1,int a2,int a3)
 {
     jia1(a1,a2,a3);
     jia1(a2,a1,);
     return;
 }
 void build(int a1,int a2,int an,int b1,int b2,int bn)
 {
     T=n+;
     cnt=;
     memset(head,,sizeof(int)*(T+));
     jia(,a1,*an);
     jia(a2,T,*an);
     jia(,b1,*bn);
     jia(b2,T,*bn);
     for(int i=;i<=n;i++)
       for(int j=;j<=n;j++)
         {
           if(ch[i][j]=='O')
             jia(i,j,);
           if(ch[i][j]=='N')
             jia(i,j,inf);
         }
     return;
 }
 int main()
 {
     for(;scanf("%d%d%d%d%d%d%d",&n,&a1,&a2,&an,&b1,&b2,&bn)==;)
     {
     a1++;
     a2++;
     b1++;
     b2++;
     for(int i=;i<=n;i++)
       scanf("%s",ch[i]+);
     build(a1,a2,an,b1,b2,bn);
     ans=;
     for(;bfs();)
       ans+=dinic(,inf);
     if(ans==*an+*bn)
       {
         build(a1,a2,an,b2,b1,bn);
         ans=;
         for(;bfs();)
           ans+=dinic(,inf);
         if(ans==*an+*bn)
           printf("Yes\n");
         else
           printf("No\n");
       }
     else
       printf("No\n");}
     return ;
 }

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