Page 206 - Computer science 868 Class 12
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121 is a palindromic number
              Enter a number
              16
              Enter p/P for Palindrome / n/N for Niven
              n
              16 is not a Niven Number



                Program 8     A happy number is a number in which the eventual sum of the square of the digits of the
                              number is equal to 1.
                              Example 1:
                                     2
                              28 = (2)  + (8)  = 4 + 64 = 68
                                           2
                              68 = (6)  + (8)  = 36 + 64 = 100
                                           2
                                     2
                              100 = (1)  + (0)  + (0)  = 1 + 0 + 0 = 1
                                      2
                                                 2
                                            2
                              Hence, 28 is a happy number.
                              Example 2:
                                     2
                              12 = (1)  + (2)  = 1 + 4 = 5
                                           2
                              Hence, 12 is not a happy number.
                              Design a class Happy to check if a given number is a happy number. Some of the members of
                              the class are given below:
                              Class name                   :   Happy
                              Data Members/Instance variables
                              n                            :   Stores the number of Member functions
                              Happy()                      :   Constructor to assign 0 to n
                              void getnum(int nn)          :   Assigns the parameter value to the number n = nn
                              int sum_sq_digits(int x)     :     Returns the sum of the square of the digits of the number
                                                               x using the recursive technique
                              void ishappy()               :    Checks  if  the  given  number  is  a  happy  number  by
                                                               calling the function sum_sq_digits(int) and displays an
                                                               appropriate message
                              Specify the class Happy giving details of the constructor(), void getnum(int), int sum_sq_
                              digits(int) and void ishappy(). Also, define a main() function to create an object and call the
                              methods to check for a happy number.


                1       import java.util.*;
                2       class Happy
                3       {

                4           int n, s, d;
                5           public Happy()

                6           {
                7               n = 0;

                8           }
                9

                10          void getnum(int nn)
                11          {



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