PAT Class A-1107 Social Clusters (30 points)

Title: 1107 Social Clusters (30 points)

Analysis : The use of and check the collection.

#include <iostream>
#include<cstring>
#include<vector>
#include<stdio.h>
#include<algorithm>
using namespace std;
int n,m,k;
int fa[100001];
int hob[100001];
int findFa(int x)
{
    
    
    if(fa[x] == x) return x;
    return findFa(fa[x]);
}
void uni(int a,int b)
{
    
    
    int f1 = findFa(a);
    int f2 = findFa(b);
    if(f1 != f2)
        fa[f1] = f2;
}
int ans[10001];
int cmp(int a,int b){
    
    return a>b;}
int main()
{
    
    
    cin>>n;
    for(int i = 1;i <= n ;i++)
        fa[i] = i;
    for(int i = 1; i <= n ;i++)
    {
    
    
        int num;
        scanf("%d:",&num);
        for(int j = 0 ; j< num ;j++)
        {
    
    
            int x;cin>>x;
            if(hob[x] == 0)
                hob[x] = i;
            else
                uni(hob[x], i);
        }
    }
    int cnt = 0;
    for(int i = 1; i <= n ;i++)
    {
    
    
        if(fa[i] == i) cnt++;
        ans[findFa(i)] ++;
    }
    sort(ans,ans + 10001,cmp);
    cout<<cnt<<endl;
    for(int i = 0;i<cnt;i++)
    {
    
    
        if(i == 0)
            cout<<ans[i];
        else
            cout<<" "<<ans[i];
    }
    return 0;
}