/* File: Power.java - March 2011 */
package l06;

/**
* Compute a^n
* using a recursive algorithm
*
* Sample usage: java l06.Power 3 21
*
* @author Michael Albert
*
*/

public class Power{

  public static void main(String[] args) {
    long a = Long.parseLong(args[0]);
    long n = Long.parseLong(args[1]);
    System.out.println(a + "^" + n + " = " + power(a,n));
  }

  public static long power(long a, long n) {
    if (n == 0) return 1;
    long p = power(a*a, n/2);
    if (n % 2 == 1) {
      p *= a;
    }
    return p;
  }

}