#include<stdio.h>
 int search(int A[],int n, int key)
{
  int i = 0;
   A[n] = key;
   while( A[i] != key) i++;
   return i != n;
}

  int main(){
  int i,n,A[10000+1],q,key,sum = 0;

  scanf("%d",&n);
  for(i = 0; i < n;i++)
  scanf("%d", &A[i]);
  
  scanf("%d", &q);
  for(i = 0; i < q;i++){
  scanf("%d",&key);
  if(search(A,n,key)) sum++;
}
  printf("%d\n",sum);

  return 0;
}