#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[10001], 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;
}
