#include <stdio.h>


int keisan(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, 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 (keisan(A, n, key))
			{
				sum++;
			}
		}
	}
	
	printf("%d\n", sum);
	return 0;
}
