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Design a class NumDude to check if a given number is a Dudeney number or not. (A Dudeney number is…

Computer Science202310 marksProgram
Design a class NumDude to check if a given number is a Dudeney number or not. (A Dudeney number is a positive integer that is a perfect cube, such that the sum of its digits is equal to the cube root of the number.) Example: $5832 = (5+8+3+2)^3 = (18)^3 = 5832$ Some of the members of the class are given below:
Class name:NumDude
**Data member/instance variable:**
num:to store a positive integer number
**Methods / Member functions:**
NumDude( ):default constructor to initialise the data member with legal initial value
void input( ):to accept a positive integer number
int sumDigits(int x):returns the sum of the digits of number ‘x’ using recursive technique
void isDude( ):checks whether the given number is a Dudeney number by invoking the function sumDigits() and displays the result with an appropriate message
Specify the class NumDude giving details of the constructor( ), void input( ), int sumDigits(int) and void isDude( ). Define a main( ) function to create an object and call the functions accordingly to enable the task.

Answer

Answer

AI
import java.util.Scanner;

class NumDude
{
    int num;   // the number to be checked

    // default constructor
    NumDude()
    {
        num = 0;
    }

    // accepts a positive integer
    void input()
    {
        Scanner sc = new Scanner(System.in);
        System.out.print("Enter a positive integer: ");
        num = sc.nextInt();
    }

    // returns the sum of the digits of x using recursion
    int sumDigits(int x)
    {
        if (x == 0)
            return 0;
        return (x % 10) + sumDigits(x / 10);
    }

    // checks whether num is a Dudeney number
    void isDude()
    {
        int s = sumDigits(num);
        if (s * s * s == num)
            System.out.println(num + " is a Dudeney number");
        else
            System.out.println(num + " is not a Dudeney number");
    }

    public static void main(String args[])
    {
        NumDude ob = new NumDude();
        ob.input();
        ob.isDude();
    }
}
sumDigits() adds the last digit (x % 10) to the sum of the remaining digits (x / 10) until x becomes 0. isDude() cubes that sum: if the cube equals the number, the sum is its cube root, so the number is a Dudeney number. Sample run:
Enter a positive integer: 5832
5832 is a Dudeney number
Objects

From ISC 2023 Computer Science Paper 1, question 6.

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