poj 3692 Kindergarten 二分图 最大独立集

poj 3692 Kindergarten

http://poj.org/problem?id=3692

 

挑选最多的互相认识的小朋友

 

补图的最大独立集

 

#include <iostream>#include <cstdio>#include <cstring>#include <queue>#include <cmath>using namespace std;int g, b, k, a[403][403], match[403], vis[403] ;char map[42][12];bool find(int u){    int i;    for( i=1; i<=g+b; i++){        if(a[u][i]==0 && !vis[i]){            vis[i]=1;            if( match[i]==-1 || find(match[i])){                match[i]=u;                return true;            }        }    }    return false;}int hungary(){    int i ,ans=0;    for(i=1; i<=g+b; i++){        memset(vis, 0, sizeof(vis));        if(find(i))            ans++;    }//cout<<ans<<endl;   // printf("%d\n", sum-ans/2);   return g+b-ans/2;}void init(){    memset(a, 0, sizeof(a));    memset(match, -1, sizeof(match));    int i, j, x, y;    for( i=0 ; i<k; i++){        scanf("%d%d", &x, &y);        a[x][y+g]=1;        a[y+g][x]=1;    }    for(i=1 ; i<=g; i++){        for(j=1; j<=g; j++){            a[i][j]=1;            a[j][i]=1;        }    }    for(i=g+1; i<=b+g; i++){        for(j=g+1; j<=b+g; j++){            a[i][j]=1;            a[j][i]=1;        }    }}int main(){ //   freopen("1.txt", "r", stdin);    int t=1;    while(scanf("%d%d%d", &g, &b, &k)&&!(g==0 && b==0 && k==0)){        init();      //  hungary();        printf("Case %d: %d\n", t++, hungary());    }    return 0;}