把某点与某几点分开的最小花费，当然想到最小割。具体怎么建图，可以画个简单的情况，然后就清楚了：
0到1不受控制，建立0->1容量为INF的边；
1到0受在0一边的一个控制面板的控制，建立1->0容量为1的边。
1 #include<cstdio> 2 #include<cstring> 3 #include<queue> 4 #include<algorithm> 5 using namespace std; 6 #define INF (1<<30) 7 #define MAXN 22 8 #define MAXM 8888 9 10 struct Edge{ 11 int v,cap,flow,next; 12 }edge[MAXM]; 13 int vs,vt,NE,NV; 14 int head[MAXN]; 15 16 void addEdge(int u,int v,int cap){ 17 edge[NE].v=v; edge[NE].cap=cap; edge[NE].flow=0; 18 edge[NE].next=head[u]; head[u]=NE++; 19 edge[NE].v=u; edge[NE].cap=0; edge[NE].flow=0; 20 edge[NE].next=head[v]; head[v]=NE++; 21 } 22 23 int level[MAXN]; 24 int gap[MAXN]; 25 void bfs(){ 26 memset(level,-1,sizeof(level)); 27 memset(gap,0,sizeof(gap)); 28 level[vt]=0; 29 gap[level[vt]]++; 30 queue<int> que; 31 que.push(vt); 32 while(!que.empty()){ 33 int u=que.front(); que.pop(); 34 for(int i=head[u]; i!=-1; i=edge[i].next){ 35 int v=edge[i].v; 36 if(level[v]!=-1) continue; 37 level[v]=level[u]+1; 38 gap[level[v]]++; 39 que.push(v); 40 } 41 } 42 } 43 44 int pre[MAXN]; 45 int cur[MAXN]; 46 int ISAP(){ 47 bfs(); 48 memset(pre,-1,sizeof(pre)); 49 memcpy(cur,head,sizeof(head)); 50 int u=pre[vs]=vs,flow=0,aug=INF; 51 gap[0]=NV; 52 while(level[vs]<NV){ 53 bool flag=false; 54 for(int &i=cur[u]; i!=-1; i=edge[i].next){ 55 int v=edge[i].v; 56 if(edge[i].cap!=edge[i].flow && level[u]==level[v]+1){ 57 flag=true; 58 pre[v]=u; 59 u=v; 60 //aug=(aug==-1?edge[i].cap:min(aug,edge[i].cap)); 61 aug=min(aug,edge[i].cap-edge[i].flow); 62 if(v==vt){ 63 flow+=aug; 64 for(u=pre[v]; v!=vs; v=u,u=pre[u]){ 65 edge[cur[u]].flow+=aug; 66 edge[cur[u]^1].flow-=aug; 67 } 68 //aug=-1; 69 aug=INF; 70 } 71 break; 72 } 73 } 74 if(flag) continue; 75 int minlevel=NV; 76 for(int i=head[u]; i!=-1; i=edge[i].next){ 77 int v=edge[i].v; 78 if(edge[i].cap!=edge[i].flow && level[v]<minlevel){ 79 minlevel=level[v]; 80 cur[u]=i; 81 } 82 } 83 if(--gap[level[u]]==0) break; 84 level[u]=minlevel+1; 85 gap[level[u]]++; 86 u=pre[u]; 87 } 88 return flow; 89 } 90 int main(){ 91 int t,n,a,b; 92 char s[11]; 93 scanf("%d",&t); 94 while(t--){ 95 scanf("%d%d",&n,&vt); 96 vs=n; NV=n+1; NE=0; 97 memset(head,-1,sizeof(head)); 98 for(int i=0; i<n; ++i){ 99 scanf("%s",s); 100 if(s[0]=='I') addEdge(vs,i,INF); 101 scanf("%d",&a); 102 while(a--){ 103 scanf("%d",&b); 104 addEdge(i,b,INF); 105 addEdge(b,i,1); 106 } 107 } 108 int res=ISAP(); 109 if(res>10000000) puts("PANIC ROOM BREACH"); 110 else printf("%d ",res); 111 } 112 return 0; 113 }