#include <stdio.h>


int main() {
	int n, q, S[10000], T[500];
	int i, j, count = 0;

	scanf("%d", &n);
	for (i = 0; i < n; i++) scanf("%d", &S[i]);
	scanf("%d", &q);
	for (i = 0; i < q; i++) scanf("%d", &T[i]);

	for (i = 0; i < q; i++) {
		for (j = 0; j < n; j++) {
			if (T[i] == S[j]) {
				count++;
				break;
			}
		}
	}

	printf("%d\n", count);

	return 0;
}