#include <cstdio>
#include <algorithm>
using namespace std;

int answer;
int n;
long long shmen[50005];
int shmenPos;

long long BISRead()
{
	long long aux;
	scanf("%lld",&aux);
	return aux;
}

int main()
{
	freopen("dtcsu.in","r",stdin);
	freopen("dtcsu.out","w",stdout);
	for (int i=1;i <= 276997;i++)
	{
		int aux = BISRead();
		if (!(aux&1)) shmen[shmenPos++] = aux;
	}
	sort(shmen,shmen+shmenPos);
	
	n = BISRead();
	for (int i=1;i<=n;i++)
	{
		int ct = BISRead();
		while (!(ct&1)) ct >>= 1;
		long long* p = lower_bound(shmen,shmen+shmenPos,ct);
		if (ct == *p) answer++;
	}
	printf("%d\n",answer);
	return 0;
}