#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;
}


	

