题解 | #数值的整数次方#

比较简单，需要分解几种情况：

public class Solution {
    public double Power(double base, int exponent) {
        if (base == 0) {
            return 0;
        }
        if (exponent == 0) {
            return 1;
        } 
        double res = 1;
        int n = exponent > 0 ? exponent : -exponent;
        while(n-- > 0) {
            res = res * base;
        }
        if (exponent > 0) {
            return res;
        } else {
            return 1/res;
        }
    }
}