POJ2524Ubiquitous Religions

裸并查集没啥说的

#include<cstdio>#include<cstring>#include<cstdlib>#include<cstdlib>#include<cmath>using namespace std;int uf[50050];int find(int x){int r=x;while(uf[r]!=r)r=uf[r];        return r;}void merge(int x,int y){int fx=find(x);int fy=find(y);if(fx!=fy)uf[fy]=fx;}int main(){int n,m,k=1;while(scanf("%d%d",&n,&m)&&(n||m)){for(int i=1;i<=n;i++)uf[i]=i;for(int i=0;i<m;i++){        int v1,v2;scanf("%d%d",&v1,&v2);merge(v1,v2);}int cnt=0;for(int i=1;i<=n;i++)if(uf[i]==i)cnt++;printf("Case %d: %d\n",k++,cnt);}}