HDU4292-Food-网络流

裸网络流题。

 #include <cstdio>
 #include <algorithm>
 #include <cstring>
 #include <queue>
 using namespace std;

 const int maxn = ;
 const int maxe = ;
 const int inf = <<;

 struct Edge
 {
     int v,cap,next;
 }edge[maxe];
 int level[maxn];
 int gap[maxn],pre[maxn],cur[maxn],head[maxn];

 int NV,NE;

 void add_edge(int u,int v,int cap)
 {
     edge[NE].v=v;
     edge[NE].cap=cap;
     edge[NE].next=head[u];
     head[u]=NE++;

     edge[NE].v=u;
     edge[NE].cap=;
     edge[NE].next=head[v];
     head[v]=NE++;
 }

 void bfs(int vt)
 {
     memset(level,-,sizeof(level));
     memset(gap,,sizeof(gap));
     level[vt]=;
     gap[level[vt]]++;
     queue<int>que;
     que.push(vt);
     while(!que.empty()) {
         int u=que.front();
         que.pop();
         for(int i=head[u]; i!=-; i=edge[i].next) {
             int v=edge[i].v;
             if(level[v]!=-)continue;
             level[v]=level[u]+;
             gap[level[v]]++;
             que.push(v);

         }
     }
 }

 int SAP(int vs,int vt)
 {
     bfs(vt);
     memset(pre,-,sizeof(pre));
     memcpy(cur,head,sizeof(head));
     int u=pre[vs]=vs,flow=,aug=inf;
     gap[]=NV;
     while(level[vs]<NV) {
         bool flag=false;
         for(int &i=cur[u]; i!=-; i=edge[i].next) {
             int v=edge[i].v;
             if(edge[i].cap&&level[u]==level[v]+) {
                 flag=true;
                 pre[v]=u;
                 u=v;
                 //  aug=(aug==-1?edge[i].cap:min(aug,edge[i].cap));
                 aug=min(aug,edge[i].cap);
                 if(v==vt) {
                     flow+=aug;
                     for(u=pre[v]; v!=vs; v=u,u=pre[u]) {
                         edge[cur[u]].cap-=aug;
                         edge[cur[u]^].cap+=aug;
                     }
                     //     aug=-1;
                     aug=inf;
                 }
                 break;
             }
         }
         if(flag)continue;
         int minlevel=NV;
         for(int i=head[u]; i!=-; i=edge[i].next) {
             int v=edge[i].v;
             if(edge[i].cap&&level[v]<minlevel) {
                 minlevel=level[v];
                 cur[u]=i;
             }
         }
         if(--gap[level[u]]==)break;
         level[u]=minlevel+;
         gap[level[u]]++;
         u=pre[u];
     }
     return flow;
 }

 int N,F,D;

 int main()
 {
     while(~scanf("%d%d%d",&N,&F,&D))
     {
         memset(head,-,sizeof head);
         NV = *N+F+D+;NE=;
         int t;
         char op[];
         for(int i=;i<=F;i++)
         {
             scanf("%d",&t);
             add_edge(,i,t);
         }
         for(int i=;i<=D;i++)
         {
             scanf("%d",&t);
             add_edge(i+F,NV,t);
         }
         for(int i=;i<=N;i++)
         {
             scanf("%s",op);
             for(int j=;j<=F;j++)
                 if(op[j-] == 'Y')
                     add_edge(j,i*-+D+F,);
         }
         for(int i=;i<=N;i++)
             add_edge(i*-+D+F,i*+D+F,);

         for(int i=;i<=N;i++)
         {
             scanf("%s",op);
             for(int j=;j<=D;j++)
                 if(op[j-] == 'Y')
                     add_edge(i*+D+F,j+F,);
         }
         printf("%d\n",SAP(,NV));
     }
 }
 /*
 4 3 3
 1 1 1
 1 1 1
 YYN
 NYY
 YNY
 YNY
 YNY
 YYN
 YYN
 NNY
 */