80求条

#include<iostream>
using namespace std;
#define ull unsigned long long
ull pow(ull x,ull n)
{
	ull p;
	if(n == 0 || x == 1){
		return 1;
	}
	if(n & 1) return x * pow(x,n-1) ;
	else
        {
	    p = pow(x,n>>1);
	    return p*p;
	}
}
int main()
{
    int a,b;
    cin>>a>>b;
    if(pow(a,b) < 1e9) cout<<pow(a,b);
    else cout<<-1;
    return 0;
}