为啥这 70 分？

#include <bits/stdc++.h>
using namespace std;
int n;
int x ;
int a[10001];
int y[10001];
int f[10001][10001];
int main() {
	cin >> n;
//	cin >> x;
	for (int i = 1; i <= n; i++) {
		cin >> x;
		a[i] += x;
//		if(x == 0) continue;
		for (int j = 1; j <= x; j++) {
			cin >> f[i][j];
//			for(int k = ; k <= )
//		if(a[a[j] == a[j]] )
		}
	}
	for (int i = 1; i <= n; ++i) {
		int sum = 0;
		for (int j = 1; j <= a[i]; ++j) {
			sum++;
			sum += a[f[i][j]];
		}
		cout << sum << ' ';
	} 
	return 0;
}

（入门赛 T6）