#include <bits/stdc++.h>
using namespace std;
#define LL             long long
#define endl           '\n'
#define all(x)         x.begin(), x.end()
#define fill(a, b)     memset(a, b, sizeof a)

const double eps = 1e-15;
const double pi = acos(-1.0);
const LL Mod = 1000000007;
const int N = 1e3 + 5;
int ks = 0;



vector <int> g[N];
bool used[N], AP[N];
int low[N], in[N], timer;

void dfs(int cur, int par = -1) {
    int son = 0;
    used[cur] = true;
    low[cur] = in[cur] = ++timer;
    for (auto to : g[cur]) {
        if (to == par) continue;
        if (used[to]) {
            low[cur] = min(low[cur], in[to]);
        } else {
            dfs(to, cur);
            low[cur] = min(low[cur], low[to]);
            son++;
            if (low[to] >= in[cur] && par != -1) AP[cur] = true;
        }
    }
    if (par == -1 && son > 1) AP[cur] = true;
}

int main() {
    ios::sync_with_stdio(0), cin.tie(0);
    int n;
    while (cin >> n && n) {
        for (int i = 1; i < N; i++) {
            g[i].clear();
            used[i] = AP[i] = false;
        }
        timer = 0;
        cin.ignore();
        while (true) {
            string s;
            getline(cin, s);
            istringstream iss(s);
            int x, y;
            iss >> x;
            if (x == 0) break;
            while (iss >> y) {
                g[x].emplace_back(y);
                g[y].emplace_back(x);
            }
        }
        for (int i = 1; i <= n; i++) {
            if (!used[i]) {
                dfs(i);
            }
        }
        int ans = 0;
        for (int i = 1; i <= n; i++) {
            if (AP[i] == true) {
                ans++;
            }
        }
        cout << ans << endl;
    }
}