求一个数的立方根

/**
      * 求一个数的立方根，利用二分法，时间复杂度在logn
      **/
    private static double getCubeRoot(double input){
        double min = 0;
        double max = input;
        double mid = 0;
        while ((max - min) > 0.0001){
            mid = (max + min) / 2;
            if(mid * mid * mid > input){
                max = mid;
                continue;
            }
            if(mid * mid * mid < input){
                min = mid;
                continue;
            }
            return mid;
        }
        return max;
    }