#include<bits/stdc++.h>
using namespace std;

int main(){
    long long a,b,ans=1;
	cin>>a>>b;
	if(a==1){
		cout<<1;
		return 0;
	}
	for(;b>0,ans<=1e9;b--) ans*=a;
	if(b!=0||ans>1e9) cout<<-1;
	else cout<<ans;
	return 0;
}