CBSE Board Class 12 Computer Science Sample Papers 2005

Sample Paper – 2005
Class – XII
Subject – COMPUTER SCIENCE
Time:3HRS                         M.M    70

  General Instruction:
      (i) All Questions are compulsory
      (ii) Programming Language : C++


Q1 a) Reusability of classes is one of the major properties of OOP. How it is implemented             2
      b) Name the header file(s) required for the given built-in functions  of C++ library             1
                 i) abc() ii)printf()
     c)  Rewrite  the given snippet after correcting the error(s) if any. Underline the each
          correction(s)                     2
                 #include<iostream.h>
                class Employee
                 {
                      int no;
                      class date
  {
                              int dd,mm,yy;
                               public:
                                  void print_date()
                                   { cout<<dd<<mm<<yy;}
                           };      
                        date DOB;
                         public :
                               date DOJ;
                              void prin()
                                {
    print_date();
                                       cout<<DOB.dd<<DOB.mm<<DOB.yy;
                                }
                 };
               void main()
                  {
                           Employee ob1;
                            date ob2;
                   }
                             
    d) What will be the output of the following program               3         
         #include<iostream.h>
        void main()
          {
                static int arr[]={0,1,2,3,4};
                int *p[] = { arr,arr+1,arr+2,arr+3,arr+4};
                int **ptr=p;
                ptr++;
                cout<<ptr-p<<*ptr-arr<<**ptr<<endl;
   *ptr++;  
                 cout<<ptr-p<<*ptr-arr<<**ptr<<endl;
  *++ptr;
                 cout<<ptr-p<<*ptr-arr<<**ptr<<endl;
                ++*ptr;
                 cout<<ptr-p<<*ptr-arr<<**ptr<<endl;
          } 
   
    e) Predict the output for the program given below :                 2
              #include <iostream.h>
              #define cube(x)(x*x*x);
              void main()
               {
                      int x=2,y,z;
                      y=cube(++x);
                      z=++y+386/cube(++x);
                     cout<<++x<<y<<z;
              }
     f) What will be the output    of the following program given below :               2
              #include<iostream.h>
              void change (int *,int);
              void main()
              {
                     int a[] = { 2,4,6,8,10 };
                    change(a,5);
                    for(int  I =0; i<5; i++) cout<<a[i];
              }
             void change(int *b, int n)
              {
                   int i ;
                   for( i =0;  i<n; i++)
                        *(b+i) = *(b+i)+5;
              }
Q2a)   What do you mean by static data members of a class ? Explain the characteristics of static
            data members                         2
     b)    Answer the questions (i) and (ii) after going through the following program :             2 
                #include<iostream.h>
                #include<string.h>
                class Hospital
                 {
           long patients_no;
           char Pat_name[35];
                         float charge;
                       
                         Hospital()   //function 1
                         {  
                             patient_no = 7164;
                             strcpy(Pat_name, “JLO”);
                             charge=12750.00;
                         }
                        publc:
                              void Enquiry()      // function2
                              {
                                    cout<<patient_no<<”:” <<Pat_name<<” : ” <<charge<<endl;
                              }
                 };
                void main()
                {
                     Hospital Hosp;          //statement 1
                     Hosp.Enquiry();       //statement  2                
                 }
                        
i)Will statement 1 initialize all the data members for the object Hosp with the value  given in Function 1?  Justify your answer suggesting the correction(s) to be made in the above code.  
ii)What shall be the possible output when the program gets executed ? Assume if required suggested correction(s) are made in the program

c) Define a class Departmental with the following specification  :                                                   4
           private data members
                Prod_name   string (45 charactes)    [ Product name]
                Listprice        long 
                Dis_Price       long  [ Discount Price]
                Net                 long  [Net Price ]
                Dis_type       char(F or N)  [ Discount type]
                Cal_price() – The store gives a 10% discount on every  product it sells. However at the
                                         time of festival  season the store gives 7% festival discount after 10%
                                         regular discount. The discount type can be checked  by tracking the
                                         discount type. Where ‘F’ means festival and ‘N’ means Non- festival .
                                         The Cal_price() will calculate the Discount Price and Net Price on the
                                         basis of the following table.
   
                public members  
Constructor  to initialize the string elements with “NULL”, numeric elements with 0 and character elements with ‘N’
Accept()  - Ask the store manager to enter Product name, list  Price and discount type . The function will invoke Cal_price() to calculate Discount Price and Net Price .
ShowBill() -  To generate the bill to the customer with all the details of his/her purchase along with the bill amount including discount price and net price.

d) Answer the questions (i) to (iv)  based on the following code:                4
           class X
           {
                 int P[20];
                 float b;
                protected :
                    char str[20];
                public:
                   X();
                   void Read();
                   void  Display();
           };
           class  E: protected X
           {
                 int No;
                 protected :
                    float S;
                 public :
                    E();
                    void EDetails();
                    void DDetails();
            };
           class P : public  X
           {
                  int Pno;
                  long  double b2;
                 pubic :
                      P();
                       void Accept();
                       void Show();
           };
          void main()
            {
                  P obj;
             }
i)Mention the members accessible by the obj  declared in main()
ii)What is the size of obj in bytes? What type of inheritance is depicted in the given snippet?
iii)If E if inherited in private visibility mode  and P  in public visibility mode from E. name the members that can be accessed by the obj.
iv)Name the member functions that can access  the data members str, if the inheritance is in multi-level format
Q3 a) Write a C++ function RevDup(int [], int) to remove the duplicate occurrence of the value
           present in an integer array, passed to the function  as a parameter.               3
               For e.g.  If array initially is X[] = { 1,1,1,7,5,2,2,6}
                        After removing  duplicate  values the array will be  X{} = { 1,7,5,2,6}

b)An array Arr[25][10]  is stored in the memory in row major order. If the address of
        Arr[10[5] is 1405 and Arr[5][3] is 625. Find the location of Arr[7][7]              4
   
c)Write an user defined Sumup(int [ ][ ]) to display sum of upper half elements of a  square
        matrix . the function will return the sum  of the values.                3

d)Evaluate the following postfix expression using stack and show the contents after
        execution of each operations                   2
                  -500, 15,7,0,-,10,2,0,-,*,+,*,+
       
e)Consider the following portion of a program, which implements Stack of Book . Write  the
definition of the function Insert() and Pop() , to insert a new information about a book and to display the information of the book written by Jane Austen                4
        struct bnode
         {
                int bno;          /* book number */
                char Aname[30];  /* Author name */
                char Bname[45]; /* Book name */
                float Price;           /* Price of the book */
                bnode *link ;
         };
        class LIBRARY
        {
            bnode * REAR,*FRONT;
            public :
                 LIBRARY() { REAR= FRONT=NULL;}
                 void Insert ();  // function to add new information to library
                 void Pop() ;     // function to display the information from the stack
                 ~LIBRARY(){ cout<<” Book not available “};
       };
Q4 a) Observe the program segment given below carefully and fill in the blanks marked by the
           statement1 and statement 2 using Seekg() and tellg() functions for performing the required 
           task                                                 1
                 #include <fstream.h>
    class Car
                  {
                       char No_Plate[15],Car_type[20];
                       public :
                         /* function to count the total no. of records in a file */
                       int Countrec();
                };
                int Car::Countrec()
                {
                     fstream file ;
                     file.open(“ Veh.dat”,ios::binary| ios::in);
                     _______________________________  //statememt1
                     int bytes = ________________________ //statement 2
                     int Count = bytes/sizeof(Car);
                     file.close();
                     return Count;
                }
b) Write a function that merges lines alternatively from two files and writes the results to new
     file.  If one file has less number of lines than the other , the  remaining lines from the larger
     file should be simply copied into the target  file.                              2

c)   Given a binary file Resume.dat containing records of all the following class Candidate type   3
            class Candidate
             {
                 char C_name[20], Post_apply[20];
                 int Expr, Sal_Exp ;
                 public :
                     void Apply()
                     {
                          gets(C_name); gets(Post_apply);
                          cin>>Expr>>Sal_Exp;
                     }
                     char * Post()
                       { return Post_apply; }
                     int Sal_Expected()
                       { return Sal_Exp; }
                     void  ShowDet()
                       {  cout<<C_name<<” “<<Post_apply<<” ”<<Expr<<” “<<Sal_Exp<<endl; }
             };
        Write a function in C++ that would read the content of Resume.dat and display the records of
        all those candidate who have applied for “Sales Manager “ with an expected salary between
        35000 .  
              
Q5 a) What is the difference between DROP And DELETE Command of SQL ? Illustrate it with
            an example                      2           
       b) Study the following tables STAFF  and SALARY  and write SQL commands  for the
          question (i) to (iv) and give output  for SQL queries  (v) to (vi)               6
 
i)Display the name of all CA’s who are working for more than  5 years
ii)Display the  number of staff joined year-wise
iii)Hike the Allowance of all female  staff working in finance sector and joined the company before 2000
iv)Display the average  salary given to the employee in each department
v)SELECT DEPT, COUNT(*) 
                     FROM STAFF
                     WHERE SEX=’m’
                     GROUP BY DEPT
                     HAVING COUNT(*) >2
     vi)           SELECT AVG(BASIC+ ALLOWANCE), QUALF
                     FROM  SALARY S1, STAFF S2
                     WHERE S1.ID=S2.ID
                     GROUP(QUALF)
        vii)          SELECT DISTINCT QUALF FROM STAFF
viii)SELECT  NAME, BASIC+ALLOWANCE
FROM STAFF S, SALARY SA
WHERE S.ID=SA.ID  AND YEAR(DOJ)<2002   

Q6  a)  State and Verify  Absorption Law in Boolean Algebra.                                                         2
       b)   Write the equivalent POS expression of following  SOP form
                  F (x,y,z)= ∑ (0,2,4,6)                                                            2
       c)  Draw the Logical circuit of the following expression with the help of NAND gate only         x+yz                                               1
       d)   Obtain the simplified form of a Boolean expression using K-Map.                            3
                     F(a,b,c,d)=∑(0,1,2,3,4,7,11,12,14)
     
Q7 a) Expand the following terminologies :                  2
GSM
CDMA
XML
URL
    b) What are Cookies?                     1
   c) Compare Optical Fiber and Coaxial transmission media                1

   d) THE CSM organization has set up its new front office at Gangtok(Sikkim) for its
        web- based activities. It has 4- Wings of buildings as shown in the diagram :

  i) Suggest a most suitable cable layout of connection between the Wings and topology.       1

  ii) Suggest the most suitable place to house the server of the organization, with suitable
      reason.                      1

  iii) Suggest the placement of the following device :             1
          Repeater
            Hub/Switch

iv)  The organization is planning to link its head office situated in Delhi with its branch office  at                      
       Gangtok. Suggest an economic way to connect it, the company is ready to compromise on the 
      speed of connectivity. Justify your answer.    1