How to write a function that can calculate power in Java. No loops

Question

I\'ve been trying to write a simple function in Java that can calculate a number to the nth power without using loops.
I then found the Math.pow(a, b) class...

Answer 1

Here is a O(log(n)) code that calculates the power of a number. Algorithmic technique used is divide and conquer. It also accepts negative powers i.e., x^(-y)

import java.util.Scanner;

public class PowerOfANumber{
        public static void main(String args[]){
                float result=0, base;
                int power;
                PowerOfANumber calcPower = new PowerOfANumber();
                /* Get the user input for the base and power */
                Scanner input = new Scanner(System.in);
                System.out.println("Enter the base");   
                base=input.nextFloat();
                System.out.println("Enter the power");
                power=input.nextInt();
                result = calcPower.calculatePower(base,power);
                System.out.println(base + "^" + power + " is " +result);
        }   
        private float calculatePower(float x, int y){ 
                float temporary;
                /* Termination condition for recursion */    
                if(y==0)
                        return 1;
                temporary=calculatePower(x,y/2);
                /* Check if the power is even */
                if(y%2==0)
                        return (temporary * temporary);
                else{
                        if(y>0)
                                return (x * temporary * temporary);
                        else
                                return (temporary*temporary)/x;
                }    
        }
}