#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;
		}
