#include <iostream>

typedef long long LL;

using namespace std;

LL pow(int a, int b)
{
    if(a == 1) return 1;
    LL s = 1;
    for(int i = 1; i <= b; i ++)
    {
        s = s * a;
        if(s > 1000000000) return -1;
    }
    return s;
}

int main()
{
    int a, b; cin >> a >> b;
    cout << pow(a, b) << endl;
    return 0;
}