#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;
}