#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <queue>
#include <cmath>
#include <vector>
using namespace std;
const int MaxM =
1e5;
int n, cnt;
bool f[
101][
101], mark[
101];
int dfn[
101], low[
101];
void tarjan(
int u,
int fa)
{
dfn[u] = low[u] = ++cnt;
int k =
0;
for (
int i =
1; i <= n; i++)
if (f[u][i] && i != fa)
{
if (!dfn[i])
{
tarjan(i, u);
k++;
low[u] = min(low[u], low[i]);
if ((k ==
2 && u ==
1) || (u !=
1 && low[i] >= dfn[u]))
mark[u] =
true;
}
else
low[u] = min(low[u], dfn[i]);
}
}
int main()
{
while (
scanf(
"%d", &n), n)
{
int u, v;
cnt =
0;
memset(mark,
0,
sizeof(mark));
memset(f,
0,
sizeof(f));
memset(dfn,
0,
sizeof(dfn));
while (
scanf(
"%d", &u), u)
while (getchar() !=
'\n')
{
scanf(
"%d", &v);
f[u][v] = f[v][u] =
true;
}
tarjan(
1,
0);
int ans =
0;
for (
int i =
1; i <= n; i++)
if (mark[i])
ans++;
printf(
"%d\n", ans);
}
return 0;
}
