#include <stdio.h>

int linearSearch(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], 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 (linearSearch(A, n, key))
      sum++;  
  }
  printf("%d\n", sum);

  return 0;
}
  