题目链接

以下是我的代码，样例都过了，但是不能AC，实在不知道问题在哪，求助！

#include<bits/stdc++.h>  //并查集
#define int long long
using namespace std;

const int maxn = 1234;
int n, s, c, a, b, k = 1;
int father[maxn], cnt[maxn];   //cnt表示集合中点的个数
bool vis[maxn];
int res1 = 0, res2 = 0;   //星座数和需要修理数

int findFather(int u){
    return father[u] == u ? father[u] : father[u] = findFather(father[u]);
}

void init(int u){
    res1 = 0, res2 = 0;
    for(int i = 1; i <= u; i++) father[i] = i, cnt[i] = 1;
    memset(vis, false, sizeof vis);
}

void Union(int a, int b){
    father[findFather(a)] = findFather(b);
    cnt[findFather(b)] += cnt[findFather(a)];
}

signed main(){
    cin >> n;
    while(n--){
        cin >> s >> c;
        init(s);
        for(int i = 0; i < c; i++){
            cin >> a >> b;
            if(findFather(a) != findFather(b)){
                Union(a, b);  //合并顶点
            }
            else vis[findFather(a)] = true;   //标记存在环的集合
        }
        for(int i = 1; i <= s; i++)
            if(father[i] == i and cnt[i] > 1){  //是根结点且集合里有多于1个顶点元素才是星系
            ++res1;
            if(vis[i]) ++res2;
        } 
        printf("Night sky #%lld: %lld constellations, of which %lld need to be fixed.\n\n", k++, res1, res2);
    }
   
    return 0;
}