package javaapplication1;
public class Example {
public static void main(String[] args) {
System.out.println(power(2, 0));
System.out.println(power(2, 1));
System.out.println(power(2, 2));
System.out.println(power(2, 3));
System.out.println(power(2, 4));
System.out.println(power(2, 5));
System.out.println(power(2, 6));
System.out.println(power(2, 7));
System.out.println(power(2, 8));
System.out.println(power(2, 9));
}
public static double power(double x, int n) {
if (n < 0)
throw new IllegalArgumentException("Illegal Power (n < 0)");
if (n == 0) return 1;
if (n == 1) return x;
if (n == 2) return x * x;
return x * power(x, n - 1);
}
}
/*
run:
1.0
2.0
4.0
8.0
16.0
32.0
64.0
128.0
256.0
512.0
*/
