#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(void)
{
	int i, n;
	int A[10000+1];
	int q, key;
	int c=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)) c++;
	}
	printf("%d\n", c);
	
	return 0;
}

