#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 n, A[10000+1], q, key, sum = 0;
	scanf("%d", &n);
	for(int i = 0; i < n; i++) scanf("%d", &A[i]);
	scanf("%d", &q);
	for(int i = 0; i < q; i++) 
	{
		scanf("%d", &key);
		if(search(A, n, key)) sum++;
		
	}
	printf("%d\n", sum);
	return 0;
}