POJ 2584

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 }