《剑指Offer》题目：数值的整数次方

public class Power {
    public static double power(double base, int exponent) {
        double res = 1.0;
        if(exponent == 0){
            return 1.0;
        }
        if(exponent > 0){
            for(int i=0; i<exponent; ++i){
                res *= base;
            }
        }
        if(exponent < 0){
            double absExponent = Math.abs(exponent);
            for(int i=0; i<absExponent; ++i){
                res *= base;
            }
            res = 1/res;
        }
        return res;
    }

    public static void main(String[] args){
        System.out.println(power(2,-3));
    }
}