AC日记——[ZJOI2009]假期的宿舍 cogs 1333
1333. [ZJOI2009] 假期的宿舍
★★☆ 输入文件:zjoi09holiday.in
输出文件:zjoi09holiday.out
简单对比
时间限制:1 s 内存限制:256 MB
思路:
网络流裸题;
来,上代码:
#include <queue> #include <cstdio> #include <cstring> #include <iostream> #include <algorithm> #define maxn 105 #define INF 0x7fffffff using namespace std; struct EdgeType { int v,f,e; }; struct EdgeType edge[maxn*maxn*4]; int n,home[maxn],s,t=maxn-1,deep[maxn],head[maxn],cnt,T; char Cget; inline void in(int &now) { now=0,Cget=getchar(); while(Cget>'9'||Cget<'0') Cget=getchar(); while(Cget>='0'&&Cget<='9') { now=now*10+Cget-'0'; Cget=getchar(); } } inline void edge_add(int u,int v,int f) { edge[++cnt].v=v,edge[cnt].f=f,edge[cnt].e=head[u],head[u]=cnt; edge[++cnt].v=u,edge[cnt].f=0,edge[cnt].e=head[v],head[v]=cnt; } bool bfs() { queue<int>que; for(int i=s;i<=t;i++) deep[i]=-1; que.push(s),deep[s]=0; while(!que.empty()) { int now=que.front();que.pop(); for(int i=head[now];i;i=edge[i].e) { if(deep[edge[i].v]<0&&edge[i].f>0) { deep[edge[i].v]=deep[now]+1; if(edge[i].v==t) return true; que.push(edge[i].v); } } } return false; } int flowing(int now,int flow) { if(now==t||flow<=0) return flow; int oldflow=0; for(int i=head[now];i;i=edge[i].e) { if(deep[edge[i].v]!=deep[now]+1||edge[i].f<=0) continue; int pos=flowing(edge[i].v,min(flow,edge[i].f)); if(pos>0) { flow-=pos; oldflow+=pos; edge[i].f-=pos; edge[i^1].f+=pos; if(flow==0) return oldflow; } } if(oldflow==0) deep[now]=-1; return oldflow; } int main() { freopen("zjoi09holiday.in","r",stdin); freopen("zjoi09holiday.out","w",stdout); in(T); while(T--) { in(n);int lit=n;cnt=1; for(int i=s;i<=t;i++) head[i]=0; for(int i=1;i<=n;i++) { in(home[i]); if(home[i]) edge_add(i+n,t,1); } int pos; for(int i=1;i<=n;i++) { in(pos); if(home[i]) { if(!pos) edge_add(s,i,1); else lit--; } else edge_add(s,i,1); } for(int i=1;i<=n;i++) { if(home[i]) edge_add(i,i+n,1); for(int j=1;j<=n;j++) { in(pos); if(pos) edge_add(i,j+n,1); } } pos=0; while(bfs()) pos+=flowing(s,INF); if(pos>=lit) printf("^_^\n"); else printf("T_T\n"); } fclose(stdin);fclose(stdout); return 0; }