注意输入的判断，多写几个if语句判断是否满足输入数据的条件
另外exp为负的时候，输入的base变为1.0/base而不是1/base
所以返回值要设置为double，base也要设为double
另外要自己定义equal，而不能用==，要去判断两个数的差的绝对值是否在一定范围内
package myPower11;
public class MyPower11 {
static boolean equal(double num1,double num2)
{
if((num1-num2>-0.0000001)&&num1-num2<0.0000001)
{
return true;
}
else
{
return false;
}
}
static double myPower(double base, int exp) throws Exception {
double result = 0;
if (equal(base,0.0) && exp < 0) {
throw new Exception("no sense");
}
if (equal(base,0.0) && exp >= 0) {
return 0;
}
if (base!=0&&exp>=0) {
result=powerCal(base, exp);
return result;
}
if (base != 0 && exp < 0) {
return powerCal(1.0 / base, -exp);
}
return result;
}
static double powerCal(double base, int exp) {
double result = 1;
if (base != 0 && exp >= 0) {
for (int i = 0; i < exp; i++) {
result *= base;
}
}
return result;
}
public static void main(String[] args) throws Exception {
// TODO Auto-generated method stub
System.out.println(myPower(2, -3));
}
}