class Solution {
public:
double my_Pow(double x, long n)
{
if(n==0) return 1.0;
if(n==1) return x;
if(n<0) return my_Pow(1/x, -n);
double result=my_Pow(x*x, n/2);
if(n%2==1) result*=x;
return result;
}
double myPow(double x, int n) {
return my_Pow(x, n);
}
};