#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;
}

