#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;
	}
	