Java 代码
class Solution {
public double Power(double base, int exponent) {
if (exponent>=0){
double res = getRes(base, exponent);
return res;
}else {
double res = getRes(base, -exponent);
return 1/res;
}
}
private double getRes(double base, int exponent) {
double a=base;//底数
int b=exponent;//指数
double res=1;//结果
while (b!=0){
if((b&1)!=0)//只要二进制不为0
res*=a;
a=a*a;
b=b>>1;
}
return res;
}
}