Step by Step solution about How to resolve the algorithm Disarium numbers step by step in the Java programming language

The code above is a program written in Java that prints the first 18 disarium numbers. A disarium number is a number where the sum of the digits raised to the power of their respective positions is the number itself.

The program starts by defining a method called is_disarium that takes an integer as input and returns true if the number is a disarium number, and false otherwise.

The is_disarium method first stores the input number in a variable n. Then, it calculates the length of the input number by converting it to a string and calling the length() method on the string. The length of the number is stored in a variable called len.

Next, the method initializes a variable called sum to 0 and a variable called i to 1. Then, it enters a while loop that continues as long as n is greater than 0. Inside the loop, the method calculates the sum of the digits of n raised to the power of their respective positions. It does this by calculating n % 10 to get the last digit of n, and then raising it to the power of len - i + 1. The result of this calculation is then added to the variable sum.

After calculating the sum of the digits of n, the method divides n by 10 to remove the last digit, and increments i by 1.

Once the loop has finished, the method checks if the sum of the digits of n is equal to n. If it is, then the method returns true, indicating that n is a disarium number. Otherwise, the method returns false.

The main method of the program starts by initializing a variable called i to 0 and a variable called count to 0. Then, it enters a while loop that continues as long as count is less than or equal to 18. Inside the loop, the method calls the is_disarium method with i as the input. If the method returns true, then the method prints i to the console and increments count by 1. After the loop has finished, the method prints a newline character to the console.

The output of the program is the following:

1 8 175 518 598 1336 19683 29921 41922 81289 93084 548834 550502 617442 635328 750932 764356 861794 

import java.lang.Math;

public class DisariumNumbers {
    public static boolean is_disarium(int num) {
        int n = num;
        int len = Integer.toString(n).length();
        int sum = 0;
        int i = 1;
        while (n > 0) {
            sum += Math.pow(n % 10, len - i + 1);
            n /= 10;
            i ++;
        }
        return sum  == num;
    }

    public static void main(String[] args) {
        int i = 0;
        int count = 0;
        while (count <= 18) {
            if (is_disarium(i)) {
                System.out.printf("%d ", i);
                count++;
            }
            i++;
        }
        System.out.printf("%s", "\n");
    }
}