哈哈

include<bits/stdc++.h>
using namespace std;
int main(){
unsigned long long d=1000000000;
int a,b;
cin>>a>>b;
unsigned long long sum=1;
for(int i=1;i<=b;i++){
sum*=a;
if(sum>d){
cout<<-1;
return 0;
}
}
cout<<sum;
return 0;
}