#include<iostream>
#include<cstring>
#include<cstdio>
using namespace std;
int dfn[105],low[105],prt[105],g[105][105];
int n,cnt,ans,son,vis[105];
void init()
{  int i,j; char ch;
   cnt=0,ans=0;son=0;
   memset(prt,0,sizeof(prt));
   memset(g,0,sizeof(g));
   memset(dfn,0,sizeof(dfn));
   memset(vis,0,sizeof(vis));
   while(scanf("%d",&i)&&i!=0)
   {  
      	while(1)
      	{	  
	  		scanf("%d%c",&j,&ch);
        	g[i][j]=1;g[j][i]=1;
        	if(ch=='\n')break;
		}
   }
}
void dfs(int u)
{  int i;
   low[u]=dfn[u]=++cnt;
   for(int i=1;i<=n;i++)
      if(g[u][i]&&prt[u]!=i)
      	{  if(!dfn[i])
         	{  
			 	prt[i]=u;
            	dfs(i);
            	low[u]=min(low[u],low[i]);
            	if(low[i]>=dfn[u])
            	{ 
					if(!vis[u]){ans++;vis[u]=1;}
               		if(u==1)son++;
            	}
         	}
         	else low[u]=min(low[u],dfn[i]);
		}
}
int main()
{  
	while(scanf("%d",&n))
   	{  
	    if(n==0)break;
      	init();
      	dfs(1);
      	if(son==1)ans--;
      	printf("%d\n",ans);
   }
}