16.数值的整数次方

class Solution {
public:
    double Power(double base, int exponent) 
    {
        	double res = 1.0;
        if (base == 0)
        {
            return 0;
        }
        if (exponent >0)
        {
            for (int i = 1;i <= exponent;i++)
            res *= base;
        }
        else if (exponent == 0)
        {
            return 1;
        }
        else
        {
            for (int i = 1;i <= -exponent;i++)
            { 
                res *= base;
            }
            res = 1 / res;
        }
        return res;
    
    }
};