Java Program – Program to Find Powers of 2

This program computes the Power of 2 by recursion. That is, 2^n for a positive integer n.

Recursive technique is used in this program

/*Power of 2 by recursion
Write a recursive mathematical definition for computing 2^n, for a positive integer n.
E.g. find 2^n
Mukesh Tekwani
*/

import java.util.Scanner;

class Powerof2
{
	public static void main(String[] args)
	{
		Scanner input = new Scanner(System.in);
		System.out.print("Enter the power of 2:");
		int n = input.nextInt();		

		System.out.println("2 raised to " + n + " is " + power(n));
	}


	public static long power(int n)
	{
		if (n == 0)  //base case
			return 1;
		else if (n == 1)
			return 2;
		else 
			return (2 * power(n - 1));
	}
}
%d