#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;
}

