Friends of Friends

problem statement is here

#include<stdio.h>
int main(){
int a,i,j,n,m[200],ar[10009]={0},ans=0,b;
scanf("%d",&n);
for(i=0;i<n;i++){
scanf("%d %d",&m[i],&a);
for(j=0;j<a;j++){
scanf("%d",&b);
ar[b]=1;
}
}
for(i=0;i<n;i++){
ar[m[i]]=0;
}
for(i=0;i<10000;i++){
if(ar[i]==1){
ans++;
}
}
printf("%d\n",ans);
return 0;
}