#include<stdio.h>
int A[1000000],n;
int binarySearch(int key)
{
	int left=0;
	int right=n;
	int mid;
	while(left<right){
		mid=(left+right)/2;
		if(key==A[mid]){return 1;}
		if(key>A[mid]){left=mid+1;}
		else if(key<A[mid]){right=mid;}
		}
		return 0;
}
int main(void){
	int i,q,k,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", &k);
		if(binarySearch(k)){sum++;}
		}
		printf("%d\n",sum);
	}
