#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(void) 
{
  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;
}
