Poj-2524-Ubiquitous (Religions)

There are n students in a school, m of which share the same religious beliefs,
Ask the maximum number of religions in this school.

Solution: basic and query sets. People with the same faith are classified as a collection,

The number of the last set is the result. Evaluate the number of sets: determine the number of root nodes and use the characteristics of the root node (the parent node is its own)

The Code is as follows:

#include<cstdio>#include<cstring>#include<iostream>using namespace std;int n,m;int f[52014];void init(){    for(int i=1; i<=n; i++)        f[i]=i;}int find(int x){    return f[x]==x?x:find(f[x]);}void unity(int a,int b){    if(find(a)!=find(b))        f[find(a)]=find(b);}int main(){    int ji=1;    while(cin>>n>>m)    {        if(n+m==0)break;        init();        while(m--)        {            int a,b;            cin>>a>>b;            unity(a,b);        }        int ans=0;        for(int i=1; i<=n; i++)            if(f[i]==i)                ans++;        cout<<"Case "<<ji++<<": ";        cout<<ans<<endl;    }    return 0;}

Poj-2524-Ubiquitous (Religions)