Check whether the given number is Armstrong number or not Example Java Program


Definition

An Armstrong number of three digits is an integer such that the sum of the cubes of its digits is equal to the number itself. For example, 371 is an Armstrong number since 3**3 + 7**3 + 1**3 = 371.

Check whether the given number is Armstrong number or not Example Program

import java.util.Scanner;

public class ArmstrongNumberCheck {
	public static boolean isArmstrong(int input) {
		String str = input + "";
		int size = str.length();
		int in = input;
		int sum = 0;
		while (in != 0) {
			int lastDigit = in % 10;
			sum = sum + (int) Math.pow(lastDigit,size);
			in = in / 10;
		}
		if (sum == input) {
			return true;
		} 
		else {
			return false;
		}
	}
	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		System.out.print("Enter a number: ");
		int inputNumber = in.nextInt();
		boolean result = isArmstrong(inputNumber);
		if (result) {
			System.out.println(inputNumber + " is an Armstrong number");
		} 
		else {
			System.out.println(inputNumber + " is not an Armstrong number");
		}
	}
}

Sample Output

Output is:
Enter a number: 5678
5678 is not an Armstrong number