#include <bits/stdc++.h>
using namespace std;
int m, n, r, gongbei = 1;
int a[105], b[105];

int gcd (int gcd_a, int gcd_b)
{
	return gcd_b == 0 ? gcd_a : gcd (gcd_b, gcd_a % gcd_b);
}

bool dfs (int k, int ceng, int num)
{
	if (ceng == r)
	{
		return 1;
	}
	
	for (int i = k + 1; i ^ m; ++i)
	{
		if (num % a[i] == 0 && dfs (i, ceng + 1, num / a[i]))
		{
			return 1;
		}
	}
	
	return 0;
}

int main ()
{
	freopen ("killer.in", "r", stdin);
	freopen ("killer.out", "w", stdout);
	scanf ("%d %d %d", &m, &n, &r);
	
	for (int i = 0; i ^ m; ++i)
	{
		scanf ("%d", &a[i]);
		gongbei = gongbei * a[i] / gcd (gongbei, a[i]);
	}
	
	for (int i = 0; i ^ n; ++i)
	{
		scanf ("%d", &b[i]);
		
		if (b[i] % gongbei == 0)
		{
			printf ("%d", i + 1);
			return 0;
		}
	}
	
	for (int i = 0; i ^ n; ++i)
	{
		if (dfs (-1, 0, b[i]))
		{
			printf ("%d ", i + 1);
			gongbei = 0; 
		}
	}
	
	if (gongbei)
	{
		printf ("0");
	}
	
	return 0;
}