#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;
}