裸的最大流

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  1 #include<cstdio>
  2 #include<cstring>
  3 #include<algorithm>
  4 using namespace std;
  5 const int N=2000,M=10000;
  6 const int inff=1<<29;
  7 int head[N],nc;
  8 struct edge
  9 {
 10     int x,y,next;
 11     int cap;
 12 } edge[M*3];
 13 void add(int x,int y,int cap)
 14 {
 15     edge[nc].x=x;
 16     edge[nc].y=y;
 17     edge[nc].cap=cap;
 18     edge[nc].next=head[x];
 19     head[x]=nc++;
 20     edge[nc].x=y;
 21     edge[nc].y=x;
 22     edge[nc].cap=0;
 23     edge[nc].next=head[y];
 24     head[y]=nc++;
 25 }
 26 int num[N],h[N],S,T,n;
 27 int findpath(int x,int flow)
 28 {
 29     if(x==T)
 30         return flow;
 31     int res=flow,pos=n-1;
 32     for(int i=head[x]; i!=-1; i=edge[i].next)
 33     {
 34         int y=edge[i].y;
 35         if(h[x]==h[y]+1&&edge[i].cap>0)
 36         {
 37             int tp=findpath(y,min(edge[i].cap,res));
 38             res-=tp;
 39             edge[i].cap-=tp;
 40             edge[i^1].cap+=tp;
 41             if(!res||h[S]==n)
 42                 return flow-res;
 43         }
 44         if(edge[i].cap>0&&h[y]<pos)
 45             pos=h[y];
 46     }
 47     if(res==flow)
 48     {
 49         num[h[x]]--;
 50         if(num[h[x]]==0)
 51         {
 52             h[S]=n;
 53             return flow-res;
 54         }
 55         h[x]=pos+1;
 56         num[h[x]]++;
 57     }
 58     return flow-res;
 59 }
 60 int Sap()
 61 {
 62     memset(h,0,sizeof(h));
 63     memset(num,0,sizeof(num));
 64     int ans=0;
 65     while(h[S]!=n)
 66         ans+=findpath(S,inff);
 67     return ans;
 68 }
 69 int main()
 70 {
 71     char cs[10]={"@SMLXT"};
 72     char s[20];
 73     while(scanf("%s",s)&&strcmp(s,"ENDOFINPUT")!=0)
 74     {
 75         int m;
 76         scanf("%d",&m);
 77         memset(head,-1,sizeof(head));
 78         S=nc=0;n=6;T=6+m;
 79         for(int i=0;i<m;i++)
 80         {
 81             scanf("%s",s);
 82             for(int j=1;j<=5;j++)
 83             {
 84                 if(s[0]==cs[j])
 85                 {
 86                     add(j,n,1);
 87                     while(j<=5)
 88                     {
 89                         add(j,n,1);
 90                         j++;
 91                         if(cs[j]==s[1])
 92                         {
 93                             add(j,n,1);
 94                             j=10;
 95                         }
 96                     }
 97                 }
 98             }
 99             add(n++,T,1);
100         }
101         for(int j,i=1;i<=5;i++)
102         {
103             scanf("%d",&j);
104             add(0,i,j);
105         }
106         if(Sap()==m)
107             printf("T-shirts rock!\n");
108         else
109             printf("I'd rather not wear a shirt anyway...\n");
110         scanf("%s",s);
111     }
112     return 0;
113 }