剑指offer: 数值的整数次方

方法1:依次相乘得出结果

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

方法2：用Math的pow方法

public class Solution {
public double Power(double base, int exponent) {
return Math.pow(base,exponent);
}
}