#include<iostream>

#include<cstdio>

#include<cstring>

#include<string>

#include<algorithm>

#include<cctype>

#include<cmath>

#include<cstdlib>

#include<queue>

#include<ctime>

#include<vector>

#include<set>

#include<map>

#include<stack>

using namespace std;

int n,dfn[],low[],cnt,sum,ans,is[];

vector<int>v[];

inline void init(){

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

      memset(dfn,,sizeof(dfn));

      memset(low,,sizeof(low));

      memset(is,,sizeof(is));

      cnt=sum=ans=;

}

inline void tarjan(int x,int fa){

      int son=;

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

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

        if(v[x][i]!=fa){

            if(!dfn[v[x][i]]){

                son++;

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

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

              if(dfn[x]<=low[v[x][i]])is[x]=;

            }else low[x]=min(low[x],dfn[v[x][i]]);

      }

      if(!fa&&son==)is[x]=;

}

int main(){

      int i,j,k;

      scanf("%d",&n);

      while(n){

          init();

          int x,y;

          scanf("%d",&x);

          while(x){

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

                scanf("%d",&y);

                v[x].push_back(y);

                v[y].push_back(x);

            }

            scanf("%d",&x);

          }

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

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

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

            if(is[i])ans++;

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

          scanf("%d",&n);

      }

      return ;

}