Page 435 - Computer science 868 Class 12
P. 435

String tobinary(int a)          :  returns the binary equivalent of number ‘a’ as String using recursive technique
                        int countones(String s)         :  using  recursive  technique, returns the  frequency  of ‘1’  in its binary  form  ‘s’
                                                           expressed as String
                        void isEvil()                   :  calls  tobinary(int)  and  countones(String)  and  prints  if  the number  is  an  evil
                                                           number or not
                        Specify the class Evilnum giving details of the methods void getnum(), String tobinary(int ) and int countones( String) and void
                       isEvil (). Also define the main() function to create an object and call the functions accordingly to enable the task.
                    8.  A number is said to be Krishnamurthy if the sum of factorial of it's digits is equal to that number. For example Number = 145
                       = 1! + 4! + 5!  = 1 + 24 + 120  = 145
                        A class called Kmurthy is defined to check if a given number is Krishnamurthy number or not. The details of the class is given
                       below:
                        Class name                      :   Kmurthy
                        Data Members/Instance variables
                        num                             :  to store the number
                        Methods/Member functions
                        void getnum()                   :  accept number in num from the user
                        int factorial(int a)            :  returns the factorial of 'a' using recursive technique
                        int sumfact(int x)              :   calls method int factorial(int) and using recursive technique calculates and returns
                                                           sum of factorial of the digits of number ‘num’
                       void check ()                    :   calls int sumfact(int x) and checks if the given number is a Krishnamurthy number
                                                           or not
                       Specify the class Kmurthy giving details of the methods void getnum(), int factorial(int )and int sumfact(int ) and void check (). Also
                       define the main() function to create an object and call the functions accordingly to enable the task.
                    9.  Monodigit numbers are numbers consisting of a single repeating digit, e.g. 77, 999, 8888 etc.
                        A  class  called  Mono  is  defined  to  check  if  a  given  number  is  monodigit  number  or  not.  The  details  of  the  class  is  given
                       below:
                        Class name                      :   Mono
                        Data Members/Instance variables
                        num                             :  to store the number
                        Methods/Member functions
                        void getnum()                   :  accept number in num from the user
                        boolean check (int n, int d)    :   using recursive technique checks if the number ‘n’ whose last digit is ‘d’ is a mono
                                                           digit number or not and returns true or false accordingly
                        void print()                    :  calls boolean check(int,int) and prints appropriate message
                        Specify the class Mono giving details of the methods void getnum(), boolean check (int, int ) and void print (). Also define the
                       main() function to create an object and call the functions accordingly to enable the task.
                    10.  A class CalSeries has been defined to calculate the sum of the series sum = 1 + x + x  + x  + ...... x n
                                                                                          3
                                                                                       2
                        Some of the members of the class are given below.                                        [ISC 2022]
                        Class name                      :   CalSeries
                        Data Members/Instance variables
                        x                               :  integer to store value of x
                        n                               :  integer to store value of n
                        sum                             :  integer to store sum of the series
                        Methods/Member functions
                        Calseries()                     :  default constructor
                        void input()                    :  to accept the value of x and n respectively
                                                                                       q
                        int power(int p, int q)         :  returns the power of p raised to q (p ) using recursive technique.
                        void cal()                      :  calculates the sum of the series by invoking the method power(), and displays the
                                                           result with an appropriate message



                                                                                                                       433
                                                                                                           Recursion   433
   430   431   432   433   434   435   436   437   438   439   440