#include<cstdio>

#include<algorithm>

#include<vector>

#include<stack>

#include<cstring>

using namespace std;

const int maxn=;

vector<int> g[maxn];

int N,M,x,y;

int low[maxn];

int dfn[maxn];

int cnt;

int scc;

int pos[maxn];

int isGedian[maxn];

int isRoot[maxn];

stack<int> st;

void init () {

    fill (low,low+maxn,);

    fill (dfn,dfn+maxn,);

    fill (pos,pos+maxn,);

    fill (isGedian,isGedian+maxn,);

    for (int i=;i<maxn;i++) g[i].clear();

    while (!st.empty()) st.pop();

    cnt=;

    scc=;

}

void tarjan (int x,int pre) {

    low[x]=dfn[x]=++cnt;

    int son=;

    st.push(x);

    for (int i=;i<g[x].size();i++) {

        if (g[x][i]==pre) continue;

        if (!low[g[x][i]]) {

            son++;

            tarjan(g[x][i],x);

            low[x]=min(low[x],low[g[x][i]]);

            if (x!=pre&&dfn[x]<=low[g[x][i]]) isGedian[x]=;

        }

        else if (!pos[g[x][i]]) low[x]=min(low[x],dfn[g[x][i]]);

    }

    if (low[x]==dfn[x]) {

        scc++;

        while () {

            int u=st.top();

            st.pop();

            low[u]=low[x];

            pos[u]=scc;

            if (u==x) break;

        }

    }

    if (x==pre&&son>) isGedian[x]=;

}

int main () {

    while (scanf("%d",&N)&&N) {

        init ();

        while (scanf("%d",&x)&&x) {

            char ch;

            while ((ch=getchar())!='\n') {

                scanf ("%d",&y);

                g[x].push_back(y);

                g[y].push_back(x);

            }

        }

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

        if (!low[i]) tarjan(i,i);

        int gedian=;

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

        if (isGedian[i]) gedian++;

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

    }

    return ;

}