POJ2584 T-Shirt Gumbo 二分图匹配（网络流）

  1 #include <cstdio>
  2 #include <cstring>
  3 #include <algorithm>
  4 
  5 const int inf=0x3f3f3f3f;
  6 const int sink=30;
  7 
  8 struct Edge
  9 {
 10     int to;
 11     int next;
 12     int capacity;
 13     
 14     void assign(int t,int n,int c)
 15     {
 16         to=t; next=n; capacity=c;
 17     }
 18 };
 19 
 20 Edge edgeList[2048];
 21 int head[40];
 22 int edgeCnt=0;
 23 
 24 inline void init()
 25 {
 26     edgeCnt=0;
 27     memset(head,-1,sizeof(head));
 28 }
 29 
 30 char cmd[20];
 31 int X;
 32 
 33 inline int idx(char s)
 34 {
 35     switch(s)
 36     {
 37     case ‘S‘: return 1;
 38     case ‘M‘: return 2;
 39     case ‘L‘: return 3;
 40     case ‘X‘: return 4;
 41     case ‘T‘: return 5;
 42     default : return -1;
 43     }
 44 }
 45 
 46 inline void addEdge(int v1,int v2,int c)
 47 {
 48     edgeList[edgeCnt].assign(v2,head[v1],c);
 49     head[v1]=edgeCnt++;
 50     edgeList[edgeCnt].assign(v1,head[v2],0);
 51     head[v2]=edgeCnt++;
 52 }
 53 
 54 bool input()
 55 {
 56     scanf("%s",cmd);
 57     if(cmd[0]==‘E‘) return false;
 58     
 59     scanf("%d",&X);
 60     for(int i=6;i<=X+5;i++) 
 61     {
 62         scanf("%s",cmd);
 63         int sm=idx(cmd[0]);
 64         int lg=idx(cmd[1]);
 65         for(int j=sm;j<=lg;j++) addEdge(j,i,inf);
 66         addEdge(i,sink,1);
 67     }
 68     for(int i=1;i<=5;i++)
 69     {
 70         int n; scanf("%d",&n);
 71         addEdge(0,i,n);
 72     }
 73     scanf("%s",cmd);
 74     return true;
 75 }
 76 
 77 int dist[40];
 78 
 79 #include <queue>
 80 
 81 int bfs()
 82 {
 83     memset(dist,0,sizeof(dist));
 84     dist[0]=1;
 85     
 86     std::queue<int> __bfs;
 87     __bfs.push(0);
 88     
 89     while(!__bfs.empty())
 90     {
 91         int cur=__bfs.front();
 92         __bfs.pop();
 93         
 94         for(int e=head[cur];e>-1;e=edgeList[e].next)
 95         {
 96             int __to=edgeList[e].to;
 97             if(edgeList[e].capacity && !dist[__to]) 
 98             {
 99                 dist[__to]=dist[cur]+1;
100                 __bfs.push(__to);
101             }
102         }
103     }
104     return dist[sink];
105 }
106 
107 int dinic_aux(int cur,int flow)
108 {
109     if(cur==sink) return flow;
110     
111     int res=0;
112     int temp=0;
113     for(int e=head[cur];e>-1;e=edgeList[e].next)
114     {
115         int __to=edgeList[e].to;
116         if(dist[__to]==dist[cur]+1 && edgeList[e].capacity)
117         {
118             temp=dinic_aux(__to,std::min(flow,edgeList[e].capacity));
119             res+=temp;
120             flow-=temp;
121             edgeList[e].capacity-=temp;
122             edgeList[e^1].capacity+=temp;
123         }
124     }
125     return res;
126 }
127 
128 inline int dinic()
129 {
130     int res=0;
131     while(bfs()) res+=dinic_aux(0,inf);
132     return res;
133 }
134 
135 const char success[]="T-shirts rock!";
136 const char fail[]="I‘d rather not wear a shirt anyway...";
137 
138 inline void solve()
139 {
140     bool proc=true;
141     while(proc)
142     {
143         init();
144         proc=input();
145         if(proc) printf("%s\n",dinic()==X?success:fail);
146     }
147 }
148 
149 int main() { solve(); return 0; }