https://pintia.cn/problem-sets/994805046380707840/exam/problems/994805068539215872?type=7&page=1

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<ll, ll> PII;
typedef vector<long long> VI;
//#define int long long
#define INF 0x3f3f3f3f
#define endl '\n'
#define N 10010
const int mod = 1e9 + 7;

ll ksm(ll a, ll b) {
    ll ans = 1;
    for (; b; b >>= 1LL) {
        if (b & 1) ans = ans * a % mod;
        a = a * a % mod;
    }
    return ans;
}

ll lowbit(ll x) {
    return -x & x;
}

//int p[N],si[N];
//int find(int x) {
//  if (x == p[x])return p[x];
//  p[x] = find(p[x]);
//  return p[x];
//}
//size[find(b)] += size[find(a)];
//p[find(a)] = find(b);

int n;
bool vis[N];
struct no1 {  //存房产数和总面积
    double area, tao;
};

struct no2 { //答案的结构体
    int id, num;

    double area, tao;
};

bool cmp(no2 a, no2 b) {
    if (a.area != b.area)return a.area > b.area; //注意有时会有精度问题则 if(abs(a.area - b.area) > 0.0001);
    return  a.id < b.id;
}

map<int, no2> mp;
vector<no1> a(N + 10);

int p[N + 10];
int find(int x) {
    if (x != p[x])p[x] = find(p[x]);

    return p[x];
}

void merge(int a, int b) {
    a = find(a);
    b = find(b);

    if (a < b)p[b] = a;
    else p[a] = b;
}

void solve() {
    cin >> n;
    a.clear();

    for (int i = 0;  i < N; i ++)p[i] = i;

    for (int i = 1; i <= n; i++) {
        int id, fa, mo;
        cin >> id >> fa >> mo;
        vis[id] = vis[fa] = vis[mo] = 1;

        if (fa != -1)merge(id, fa);
        if (mo != -1)merge(id, mo);

        int k;
        cin >> k;
        for (int j = 1; j <= k; j ++) {
            int son;
            cin >> son;
            vis[son] = 1;

            merge(id, son);
        }

        double tao, area;
        cin >> tao >> area;


        a[id] = {area, tao};
//      cout <<  a[id].area << " " << a[id].tao << endl;
    }

    for (int i = 0; i < N; i ++) {
        if (vis[i]) {
            int t = find(i);

            mp[t].id = t;
            mp[t].num ++;
            mp[t].area += a[i].area;
            mp[t].tao += a[i].tao;
        }
    }

    vector<no2> res;

    for (auto t : mp) {
        t.second.tao /= 1.0 * t.second.num;
        t.second.area /= 1.0 * t.second.num;

        res.push_back(t.second);
    }

    sort(res.begin(), res.end(), cmp);


    cout << res.size() << endl;
    for (auto t : res) {
        printf("%04d %d %.3lf %.3lf\n", t.id, t.num, t.tao, t.area);
    }



}

signed main() {

//  ios::sync_with_stdio(false);
//  cin.tie(0), cout.tie(0);

    int T = 1;
//  cin >> T;
    while (T --)

        solve();

    return 0;
}