#include <stdio.h>

#include <algorithm>

#include <vector>

#include <string.h>

using namespace std;

#define N 10100

vector<vector<int> >G;

int n, dfn[N], low[N], Time, father[N], vis[N];

void Init()

{

    G.clear();

    G.resize(n+);

    memset(dfn, , sizeof(dfn));

    memset(low, , sizeof(low));

    memset(father, , sizeof(father));

    memset(vis, , sizeof(vis));

    Time = ;

}

void Trajin(int u, int fa)

{

    father[u] = fa;

    dfn[u] = low[u] = ++Time;

    int i, len = G[u].size(), v;

    for(i=; i<len; i++)

    {

        v = G[u][i];

        if(!dfn[v])

        {

            Trajin(v, u);

            low[u] = min(low[u], low[v]);

        }

        else if(fa!=v)

            low[u] = min(low[u], dfn[v]);

    }

}

int main()

{

    while(scanf("%d", &n), n)

    {

        Init();

        int a, b;

        char x;

        while(scanf("%d", &a), a)

        {

            while(scanf("%d%c", &b, &x))

            {

                G[a].push_back(b);

                G[b].push_back(a);

                if(x=='\n')break;

            }

        }

        Trajin(, );

        int ans = , RootSon = ;

        for(int i=; i<=n; i++)

        {

            if(father[i]==)RootSon++;

            else if(dfn[father[i]]<=low[i])

                vis[father[i]] = ;

        }

        if(RootSon>)ans++;

        for(int i=; i<=n; i++)

            if(vis[i])ans++;

        printf("%d\n", ans);

    }

    return ;

}