hdoj 1213 How Many Tables

题目链接：​​How Many Tables​​

题目大意：有一堆乱七八糟的朋友关系，然后问你一共有多少个朋友圈

题目思路：并查集裸题，直接写就好了

#include <bits/stdc++.h>

using namespace std;

int t,a,b,m,n,father[1005];

int Find(int x){
    if(x == father[x]) return x;
    return father[x] = Find(father[x]);
}

void join(int x,int y){
    int p = Find(x),q = Find(y);
    if(p!=q) father[p] = q;
}

int main(){
    scanf("%d",&t);
    while(t--){
        scanf("%d%d",&n,&m);
        int Set = n;
        for(int i = 0;i <= n;i++)
            father[i] = i;
        while(m--){
            scanf("%d%d",&a,&b);
            if(Find(a) != Find(b)) join(a,b),Set--;
        }
        printf("%d\n",Set);
    }
    return 0;
}