2010 Computer Science Class - XII Set - I CBSE Question paper

2010 Computer Science Class - XII Set - I CBSE Question paper
Computer science
Class: XII (SET – I)

Time Duration: 3 Hours Maximum Marks : 70

Instructions:
(i) All Questions are Compulsory.
(ii) Programming Language : C++
----------------------------------------------------------------------------------------------------

1.(a) Distinguish between an object and a class.
(b) How does a pointer variable differ from a simple variable?
(c) What is an inline function? Specify the conditions when you can not create inline
function?
(d) What are the advantages offered by inheritance?
(e) What is a parameter? Differentiate between an actual and a formal parameter with an
example? (2 X 5 = 10)

2. (a) Write the names of the header files to which the following belong :
(i) gets() (ii) remove() (iii) abs() (iv) isupper()

(b) What will be the output of the following program :
#include
#include
#include
#include
void changestring(char text[], int &counter)
{
char *ptr = text;
int length=strlen(text);
for(;counter
{
*(ptr+counter) = toupper(*(ptr+counter));
}
}
void main()
{
clrscr();
int position = 0;
char message[]=”Mouse Fun”;
changestring(Message,position);
cout<<<” @ “<
}

(c). What will be the output of the following program :
#include
void main()
{
int var1=5,var2=10;
for(int i=1;i<=2;i++)
{
cout<<<”\t”<<--var2<
cout<<<”\t”<<++var1<
}
}

(d) Write definition for a function SUMSEQUENCE() in C++ with two arguments/parameters – double x and int n. The function should return a value of type double and it should perform sum of the following series :
1/x – 3!/x2 + 5!/x3 – 7!/x4 + 9!/x5 - …………………. Up to n terms.
(Note : The symbol ! represents Factorial of a number i.e. 5! = 5*4*3*2*1)
2
(e) Write a C++ function that converts a decimal number to the hexadecimal number.
2

3.
(a) Define the following terms : (i) Candidate Key (ii) Alternate Key 2
(b) Differentiate between DDL and DML 1
(c) What is relational data model? 1
(d) What are views? How are they useful? 1

TABLE : EMP
EMPNO ENAME JOB MGR HIREDATE SAL COMM DEPTNO
7839 REA MANAGER 67 12-DEC-98 5000 0 10
1234 PREM CLERK 87 11-FEB-77 12000 1500 20
6754 SITA MANAGER 89 12-MAR-99 10000 1000 20
6574 GITA SALESMAN 98 11-JUN-99 9000 0 30
9876 HONEY CLERK 65 12-JUN-00 12000 800 20
8976 REEMA SALESMAN 91 10-SEP-88 6000 100 30

(e) Display names of employees whose names include either of the substring “TH” or “LL”.
(f) Display data of all employees sorted by their department, seniority and salary.
(g) Find all the employees who have no manager.
(h) To display all employees who were hired during 1995.
(i) Show the average salary for all departments with more than 3 people for a job.
(j) Find out number of employees having ‘MANAGER’ as job.
(k) Create view DEPT20 with name and the salary of employees for dept 20.
(l) Display department no. and number of employees in each department.
(m) Find the output of the following :
1. SELECT SYSDATE FROM DUAL;
2. SELECT ENAME,SAL FROM EMPLOYEE WHERE DEPTNO=20;
3. SELECT COUNT(*) FROM EMP;
4. SELECT AVG(SAL) FROM EMP; 10

4.
1. By means of truth table, demonstrate the validity of the following Postulates/Laws of
Boolean Algebra.
(a) The Distributive Law
(b) Absorption Law 2
2. State and prove the De Morgan’s Theoram (Any One) Algebraically. 2
3. Obtain a simplified form for the following Boolean Expression using K – Map: F(u,v,w,z) = ?(0,3,4,5,7,11,13,15) 2
4. Obtain a simplified form for a Boolean expression : F(X,Y,Z,W) = ?(0,1,3,5,6,7,10,14,15) 2
5. Design a circuit to realize the following : F(A,B,C) = AB + AC’ + B’A’C 2
6. Show A(B’+C) using NOR gate only. 2
7. Reduce X’Y’Z’ + X’YZ’+XY’Z’ + XYZ’ = Z’ 2
8. Write dual of the following Boolean Expression (x+y’+z)(x+y) 1

5. (a) Define a class in C++ with the following description :
• A data member Flight Number of type integer.
• A data member Destination of type string
• A data member Distance of type float
• A data member Fuel of type float
A member function CALFUEL() to calculate the value of Fuel as per the following criteria :
Distance Fuel
<=1000 500
more than 1000 and <=2000 1100
more than 2000 2200
Public Members
• A function FEEDINFO( ) to allow user to enter values for the Flight Number, Destination, Distance & call function CALFUEL() to calculate the quantity of Fuel.
• A function SHOWINFO( ) to allow user to view the content of all the data members.

(b) Define a class Test in C++ with the following description :
Private Members
(i) Test Code of type integer
(ii) Description of type string
(iii) Noofcandidate of type integer
(iv) Centerreqd (number of centers required) of type integer
(v) A member function CALCNTR( ) to calculate and return the number of centers as (NOOFCANDIDATES /100+1)
Public Members
? A function SCHEDULE() to allow user to enter values for Test Code, Description, Noofcandidates & call function CALCNTR( ) to calculate the number of canters.
? A function DISPTEST( ) to allow user to view the content of all the data members.

6.
class PUBLISHER
{
char pub[12];
double turnover;
protected:
void register( );
public:
PUBLISHER( );
void enter( );
void display( );
};
class BRANCH
{
char city[20];
protected:
float employees;
public:
BRANCH( );
void haveit( );
void giveit( );
};
class AUTHOR: private BRANCH, public PUBLISHER
{
int acode;
char aname[20];
float amount;
public:
AUTHOR( );
void start( );
void show( );
};

(i) Write the names of data members. Which are accessible from objects belonging to class AUTHOR.
(ii) Write the names of all the members functions which are accessible from objects belonging to class BRANCH.
(iii) Write the names of all the members which are accessible from members functions of class AUTHOR.
(iv) How many bytes will be required by an object belonging to class ATHOR?
(v) Write the public members of the class AUTHOR