[Luogu2055] [zjoi2009] dormitory for holidays

Portal

All students have beds to let people who know themselves go to bed. Students who are not in school do not occupy beds.

Consider creating a bipartite graph, matching the person's bed, and finding the maximum match. According to the question, everyone should be arranged, So there cannot be a match.

#include <cstdio>#include <cstring>#include <algorithm>#define MAXN 55int Link[MAXN],vis[MAXN];int Graph[MAXN][MAXN];int is_out[MAXN],is_s[MAXN];int T,N;bool Hungary(int u){    for(register int i=1;i<=N;++i){        if(is_s[i]==0||vis[i]==1)continue;        if(Graph[u][i]==0)continue;        vis[i] = 1;        if(Link[i]==0||Hungary(Link[i])){            Link[i] = u;            return true;        }    }    return false;}int main(){    scanf("%d",&T);    for(register int k=1;k<=T;++k){        std::memset(Link,0,sizeof(Link));        scanf("%d",&N);        for(register int i=1;i<=N;++i)scanf("%d",&is_s[i]);        for(register int i=1;i<=N;++i)scanf("%d",&is_out[i]);        for(register int i=1;i<=N;++i)        for(register int j=1;j<=N;++j)scanf("%d",&Graph[i][j]);        for(register int i=1;i<=N;++i)Graph[i][i] = 1;        bool flag = true;        for(register int i=1;i<=N;++i){            if(is_s[i]==1&&is_out[i]==1)continue;            std::memset(vis,0,sizeof(vis));            if(!Hungary(i)){                flag = false;                break;            }        }        if(flag)puts("^_^");        else puts("T_T");    }    return 0;}

[Luogu2055] [zjoi2009] dormitory for holidays