Write a Program to print All Armstrong numbers between 1 to 1000


This Java program prints all the Armstrong numbers between 1 to 1000. An Armstrong number is a number that is equal to the sum of its own digits each raised to the power of the number of digits.

  • The program starts by declaring and initializing the integer variables i and arm to 1. It then prints a message to the console indicating that it is going to print all the Armstrong numbers between 1 and 1000.
  • The program then enters a while loop that runs until i is less than 1000. Within the loop, the program calls the armstrong() method with the current value of i as its argument, and stores the result in the arm variable.
  • The armstrong() method calculates the sum of the cube of each digit of the input number using a while loop. Once the calculation is complete, the method returns the result.
  • The program then checks if the value of arm is equal to the current value of i. If it is, the program prints the current value of i to the console.
  • Finally, the program increments the value of i by 1 and the while loop repeats until i is no longer less than 1000.

Source Code

class All_Armstrong
{
	public static void main(String arg[])
	{
		int i=1,arm;
		System.out.println("Armstrong Numbers Between 1 to 1000");
		while(i<1000)
		{
			arm=armstrong(i);
			if(arm==i)
				System.out.println(i);
			i++;
		}
	}
	static int armstrong(int num)
	{
		int x,a=0;
		while(num!=0)
		{
			x=num%10;
			a=a+(x*x*x);
			num/=10 ;
		}
		return a;
	}
}

Output

Armstrong Numbers Between 1 to 1000
1
153
370
371
407

Example Programs