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

int main(){
    int a,b;
    
    cin>>a>>b;
    if (a==1) cout<<1<<endl;
    else{
        long long ret=1;
        for(int i=1;i<=b;i++){
            ret=ret*a;
            if(ret>1e9){
                cout<<-1<<endl;
                return 0;
            }
        }
        cout<<ret<<endl;
    }
   
}