#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[100001],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);
}