#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[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 (search(A, n, key) ) {
			sum++;
		}
	}
	printf("%d\n", sum);
	
	return 0;
}
