Java Program to generate 3-digit Armstrong Numbers!

GENERATING THREE DIGIT ARMSTRONG NUMBERS

AIM:  To write a program in Java to generate three-digit Armstrong Numbers.

Note:  Armstrong numbers are three digit numbers whose sum of cubes of the individual digits of the number is equal to the number itself.  For Example, 153 is an Armstrong number.

            (153 = 1³ + 5³ + 3³ = 1 + 125 + 27 = 153, an Armstrong number)

ALGORITHM:

1. Declare two variables n, m and sum of type int in method main()
2. Use a for loop with an index variable i that starts with value 100 and end with value 999 for the following:
1. Take the current value of i as the next number to be verified.  This is done by assigning the current value of i to n
2. Initialize the value of sum to 0 (sum=0)
3. Repeat the following  until n>0

                                                              i.      Separate the right most digit of n by applying modulus operator on n (n%10) and store it in m

                                                            ii.      Add the cubic value of m to sum

                                                          iii.      Reduce the value of n by 10 (n/10).  Let n has the remaining digits except the right most digit.

3. Check whether the value of i (i.e., the current three digit number) and the value of sum are equal.  If so, print the number as the next Armstrong number.

PROGRAM:

public class ArmstrongNos {

    public static void main(String[] args) {

        int n, m, sum;

        System.out.println("Three Digit Armstrong numbers are : ");

        for(int i=100; i<=999; i++)

        {

            n = i;

            sum = 0;

            while(n!=0)

            {

                m = n%10;

                sum = sum + (int) Math.pow(m, 3);

                n = n/10;

            }

            if(sum == i)

                System.out.print(i+ " ");

        }

        System.out.println("");

    }

}

Sample Run: