Leetcode Pow(x, n)

public class Solution {
    public double myPow(double x, int n) {
        if(n < 0) {
            return 1/power(x, -n);
        }else{
            return power(x, n);
        }
    }
    
    private double power(double x, int n){
        if(n == 0) {
            return 1;
        }
        double v = power(x, n/2);
        if( n % 2 == 0) {
            return v * v;
        }else {
            return v * v * x;
        }
    }
}