loj10100 网络

#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[110],low[110],cnt,sum,ans,is[110];
vector<int>v[110];
inline void init(){
      for(int i=0;i<=100;i++)v[i].clear();
      memset(dfn,0,sizeof(dfn));
      memset(low,0,sizeof(low));
      memset(is,0,sizeof(is));
      cnt=sum=ans=0;
}
inline void tarjan(int x,int fa){
      int son=0;
      dfn[x]=low[x]=++cnt;
      for(int i=0;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]=1;
            }else low[x]=min(low[x],dfn[v[x][i]]);
      }
      if(!fa&&son==1)is[x]=0;
}
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=1;i<=n;i++)
            if(!dfn[i])tarjan(i,0);
          for(i=1;i<=n;i++)
            if(is[i])ans++;
          printf("%d\n",ans);
          scanf("%d",&n);
      }
      return 0;
}