#include <iostream>
using namespace std;
int main ()
{
	long long a, b, sum1 = 1;
	long long sum2 = 1000000000;
	cin >> a >> b;
	for (int i = 1; i <= b; i++)
	{
		sum1 *= a;
	}
	if (sum1 > sum2)
	{
		cout << "-1";
	}
	else
	{
		cout << sum1;
	}
	return 0;
}

70分是为什么