#include<bits/stdc++.h>
#define ll long long
using namespace std;
ll n,m,ans=1;
int main(){
 	//freopen(".in","r",stdin);
	//freopen(".out","w",stdout);
	scanf("%d%d",&n,&m);
	if(n==1){
		cout<<"1";
		return 0;
	}
	if(m>=30){
		cout<<"-1";
		return 0;
	}
	if(n>=31623&&m>=2){
		cout<<"-1";
		return 0;
	}
	for(int i=1;i<=m;i++){
		ans=ans*n;
		if(ans>1e9){
			cout<<-1;
			return 0;
		}
	}
 cout<<ans;
    return 0;
}