HDU——T 1054 Strategic Game

 1 #include <cstring>
 2 #include <cstdio>
 3 
 4 const int N(2555);
 5 int n,sumedge,head[N];
 6 struct Edge
 7 {
 8     int v,next;
 9     Edge(int v=0,int next=0):v(v),next(next){}
10 }edge[233333];
11 inline void ins(int u,int v)
12 {
13     edge[++sumedge]=Edge(v,head[u]);
14     head[u]=sumedge;
15     edge[++sumedge]=Edge(u,head[v]);
16     head[v]=sumedge;
17 }
18 
19 int match[N];
20 bool vis[N];
21 bool find(int u)
22 {
23     for(int v,i=head[u];i;i=edge[i].next)
24         if(!vis[v=edge[i].v])
25         {
26             vis[v]=1;
27             if(!match[v]||find(match[v]))
28             {
29                 match[v]=u;
30                 return true;
31             }
32         }
33     return false;
34 }
35 
36 inline void read(int &x)
37 {
38     x=0; register char ch=getchar();
39     for(;ch>‘9‘||ch<‘0‘;) ch=getchar();
40     for(;ch>=‘0‘&&ch<=‘9‘;ch=getchar()) x=x*10+ch-‘0‘;
41 }
42 
43 int main()
44 {
45     for(;~scanf("%d",&n);)
46     {
47         int ans=0;sumedge=0;
48         for(int u,k,i=0;i<n;i++)
49         {
50             read(u),read(k);
51             for(int v;k--;)
52                 read(v),ins(u+1,v+1);
53         }
54         for(int i=1;i<=n;i++)
55         {
56             if(find(i)) ans++;
57             memset(vis,0,sizeof(vis));
58         }
59         memset(edge,0,sizeof(edge));
60         memset(head,0,sizeof(head));
61         memset(match,0,sizeof(match));
62         printf("%d\n",ans>>1);
63     }
64     return 0;
65 }