#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;
}
       

