package Maths;

/**
 * An Armstrong number is equal to the sum of the cubes of its digits. For example, 370 is an
 * Armstrong number because 3*3*3 + 7*7*7 + 0*0*0 = 370. An Armstrong number is often called
 * Narcissistic number.
 */
public class Armstrong {

 public static void main(String[] args) {
 assert (isArmStrong(0));
 assert (isArmStrong(1));
 assert (isArmStrong(153));
 assert (isArmStrong(1634));
 assert (isArmStrong(371));
 assert (!isArmStrong(200));
 }

 /**
 * Checks whether a given number is an armstrong number or not.
 *
 * @param number number to check
 * @return {@code true} if given number is armstrong number, {@code false} otherwise
 */
 private static boolean isArmStrong(int number) {
 int sum = 0;
 int temp = number;
 int numberOfDigits = 0;
 while (temp != 0) {
 numberOfDigits++;
 temp /= 10;
 }
 temp = number; /* copy number again */
 while (number > 0) {
 int remainder = number % 10;
 int power = 1;
 for (int i = 1; i <= numberOfDigits; power *= remainder, ++i)
 ;
 sum = sum + power;
 number /= 10;
 }
 return sum == temp;
 }
}