solution of Computer Science (12th)sample paper new pattern(2013)
SAMPLE PAPER – SET
MARKING
SCHEME
COMPUTER
SCIENCE [CODE–083]
CLASS –
XII
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Max Time
: 3 hours Max Marks : 70
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1.
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(a) Write
the prototype of a function named Percent, which takes an integer as value
parameter and return a float type value. The parameter should have a default
value 10.
AAns:- float Percent (int x=10);
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(2)
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1(b) Write the names of header files, which are NOT necessary to run the
following program:
#include <iostream.h>
#include <stdio.h>
#include <string.h>
#include <math.h>
void main()
{
char STR[80];
gets(STR);
puts(strrev(STR));
}
Ans:-
<iostream.h>
<math.h>
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(1)
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1(c) Tarunaj
has just started working as programmer in the JAGAT WORLD SOFTWARE company.
In the company, he has got his first assignment to develop a small C++ module
to find the biggest number out of a given set of numbers stored in a one
dimensional array. Somehow he has committed a few logical mistakes while
writing this code and so he is not getting the desired result from the code.
Find out the mistakes and correct this C++ code so that it provides the
desired result (do not add any new statement in the code). Underline each
correction made:
{
int a = 2, b = 5;
demo(::a,a,b); //3,2,5 ::a means global version (declared out of
main())of a will be reffered
demo(::a,a,b);//8,2,10
}
Answer: 3*5*10
8*10*20
2.(a) What
do you understand by Data Encapsulation and Data Hiding? Also, give a
suitable C++ code to illustrate both.
Data Encapsulation:
·
Data Encapsulation combines data and functions into a
single unit called Class.
·
Data Encapsulation enables the important concept of
data hiding possible.
Define
a class having both data and functions as members make all data members
private to hide its visibility/accessibility
from outside the class. Make some member function as public that will
be used to interact with the outside world from main function.
Data Encapsulation: Wrapping up of data and functions together in a single
unit is known
as Data Encapsulation. In a
class, we wrap up the data and functions together
in a single
unit.
Data Hiding:
Keeping the data in private visibility mode of the class to prevent it from
accidental change is known as Data Hiding.
class Computer
{char CPU[10];int RAM;
public: Data
Encapsulation
void STOCK();
void SHOW();
};
( ½ Mark each for appropriate definitions)
(1 Mark
for appropriate example
showing both)
(2)(b) What
is constructor overloading? Give an example to illustrate the same.
……………………………………………………………..ANSWER—EXAMPLE……………………………………………..
class Exam
{char Subject[20] ;
int Marks ;
public :
Exam() //
Function 1
{
strcpy(Subject,
“Computer” ) ;
Marks = 0 ;
}
Exam(char P[ ]) //
Function 2
{
strcpy(Subject, P) ;
Marks=0 ;
}
Exam(int M) //
Function 3
{
strcpy(Subject,
“Computer”) ;
Marks = M ;
}
Exam(char P[ ], int M)
//
Function 4
{
strcpy(Subject, P) ;
Marks = M ;
} };
(2)(c)
Define a class HandSet in C++ with following description:
Private
members:
Make- of
type string
Model- of
type string
Price- of
type long int
Rating- of
type char
Public
Members:
Function
Read_Data to read an object of HandSet type.
Function
Display() to display the details of an object of HandSet type.
Function
RetPrice() to return the value of Price of an object of HandSet type. (4)
---------------------------------
ANSWER
2(C)--------------------------------------------------------------------
class HandSet {
private :
char Make[20];
char Model[20];
long int Price;
char Rating;
public:
void Read_Data()
{cout<<”\n
Enter Make , Model ,Price and Rating :
\n“ ;
gets(Make); gets(Model); cin>>Price;
cin>>Rating;}
void Display()
{cout<<”\n Make : “<<Make<<”\n Model
: “<<Model<<”\n Price”<< Price<<”\n Rating : “ <<Rating;}
long int RetPrice() { return Price;}
2(d)
Consider the following class counter:
class
counter
{ protected
:
unsigned int
count;
public :
counter()
{ count = 0;
}
void
inc_count()
{ count++; }
int
get_count()
{ return
count; }
};
Write code
in C++ to publically derive another class new_counter from class counter.
Class new_counter should have the following additional function members in
the public visibility mode:
(i) A
parameterized constructor to initialize the value of count to the value of
parameter.
(ii)
dec_count() to decrease the value of data member count by 1.
(iii)
Reset() to set the value of data member count to 0.
………………………ANSWER 2(D ) ……………………………..
class new_counter : public counter
{
public:
new_counter(unsigned int x)
{
count=x;
}
void dec_count(){count--;}
void Reset() {count=0;}
};
3 (a) Write
a function TRANSFER(int A[], int B[], int Size) in C++ to copy the elements
of array A into array B in such a way that all the negative elements of A
appear in the beginning of B, followed by all the positive elements, followed
by all the zeroes maintaining their respective orders in array A. For
example:
If the
contents of array A are:
7, -23, 3,
0, -8,-3,4, 0
The contents
of array B should be
-23 , -8,
-3, 7, 3, 4, 0
------------------------------------------------ANSWER
3(a)----------------------------------------------------
#include<iostream.h>
#include<conio.h>
void transfer(int a[],int b[],int size);
void main()
{
int a[]=
{7, -23, 3, 0, -8,-3,4, 0},b[8];
transfer(a,b,8);
for(int i=0;i<8;i++)
cout<<b[i]<<'\t';
getch();
}
void transfer(int a[],int b[],int size)
{
int k=0;
for(int i=0;i<size;i++)
if(a[i]<0)
{
b[k]=a[i];
k++;
}
for(int i=0;i<size;i++)
if(a[i]>0)
{
b[k]=a[i];
k++;
}
for(int i=0;i<size;i++)
if(a[i]==0)
{
b[k]=a[i];
k++;
}
}
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3(b) Each element of the array A[8][6] is stored using 4
bytes of memory. If the element A[2][4] is stored at location 936, find the
address of A[5][1]. Assume that the array is stored column-wise.
----------------------------------------------------------ANSWER
3(b)---------------------------------------------------------------------
Given : Size of each element (w) = 4,
No of colums (Nc) = 6, No. of
rows(Nr) =8
Actual Physical Address of
A[2][4] in Column Major scheme =Base
Address + w * [(i -0) +Nr * (j-0)]
Here, i=2 and j=4;
Actual Physical Address of A[2][4] in Column Major scheme =936
So, using formula we
calculate Basic Address (BA)--
936= BA+4(2+8*4)
936=BA+4*34
BA=936-136
BA=800
Actual Physical Address of Element A[5][1] in Column Major
scheme =
Base Address + w * [(i -0) +Nr *
(j-0)]
Here, i=5 and j=1; BA=800
Actual
Physical Address of Element A[5][1] in
Column Major scheme =800+4[5+8*1]
=800+4*13
=852 (Answer)
3(c) Write a function in C++ to perform Insert operation in
a circular Queue containing Player’s information (represented with the help of
an array of structure PLAYER).
-----------------------------ANSWER 3 ( c )
-----------------------------------------------------------
#include<iostream.h>
#include<conio.h>
struct
PLAYER
{
long
PID; //Player ID
char
Pname[20]; //Player Name
} p[3];
int
rear=-1, front=-1;
void
insert( PLAYER p1, int size)
{
if((front==0
&& rear==size-1)||front==rear+1)
{
cout<<"\n
over flow" ;
return;
}
else
if(front==-1)
front=rear=0 ;
else
if(rear==size-1)
rear=0;
else
rear++;
p[rear]=p1;
cout<<"\n
player successfully added";
}
Note: Here , main program is given only four output testing purpose. Please don’t write main
program in examination..write only the definition of function asked.
4.(a) A binary file “Students.dat” contains data of 10
students where each student’s data is an object of the following class:
class Student
{
int Rno;char Name[20];
public:
void EnterData() {cin>>Rno; cin.getline(Name,20);
void ShowData() {cout<<Rno<<” -
”<<Name<<endl;}
};
With reference to this information, write output of the
following program segment:
ifstream File; Student S;
File.open(“STUDENTS.DAT”,ios::binary|ios::in);
File.seekg(0, ios::end);
// it sets the Read File pointer at the end of file—last char in file
Cout<<File.tellg(); //it displays how far is the READ FILE POINTER from the
beginning of file (in terms of bytes)
-----------------------------------
ANSWER -4 (a)-----------------------------------------------------------
Cout<<File.tellg();
//it displays how far is the READ FILE
POINTER from the beginning of file (in bytes)—here in the
Current
situation it displays total no. of bytes/char present in the file.
Total
no. of records (i.e. objects of class student ) present in the “STUDENTS.DAT” =
10
Size of
each record= sizeof(student object)= sum of size of each data
member=sizeof(int)+sizeof(Name)=4+20=24
NOTE : SIZE OF “INT” is different in different
compilers. For BORLAND C++ it is “4 Bytes”
Size of file=position of last char in file= No of
Records stored in file * Size of each Record
=10 * 24 =240 Bytes (In BC++)--- Answer = 240
4(b) Write a function in C++ to count the number of lines starting
with a digit in a text file “DIARY.TXT”.
-----------------------------------
ANSWER -4 (B)-----------------------------------------------------------
void countLines()
{
ifstream f;
f.open("DIARY.TXT");
int count=0;
char line[200];
while(f)
{
f.getline(line,100);
if (isdigit(line[0])) count++;
}
cout<<"\n No of lines
starting with digit = "<<count;
f.close();
}
4 (c) Given a binary file “STUDENT.DAT”,
containing records of the following class Student type:
class student
{ char S_admno[10]; //Admission no. of
student
char S_Name[20]; //Name of student
int Percentage; //Marks percentage of student
public:
void
EnterData()
{
gets(S_admno); gets(S_Name); cin>>Percentage;
}
void
DisplayData()
{
cout<<setw(12)<<S_admno;
cout<<setw(32)<<S_Name;
cout<<setw(3)<<Percentage<<endl;
}
int
Ret_Per() {return Percentage;}
};
Write a
function in C++ that would read contents of the file “STUDENT.DAT” and display
the details of those students whose percentage is above 75.
………………………………………….
ANSWER 4 ( c ) ……………………………………………………………………….
void
DisplayFile()
{
ifstream
f;
f.open("STUDENT.DAT ",ios::binary);
while(1)
{
f.read((char*)&p,sizeof(p));
if(f.eof()==1)
break;
else
if(p.Ret_Per()>75) p.DisplayData();
}
f.close();
}
5. (a)-(i)- (ANSWER) NO, “MNo”
column cannot be made as Primary Key because valus in this column are not
UNIQUE, value 102 is repeated more than one time. It is violating the Primary
Key constraints so cannot act as Primary Key.
(Same member can purchase many
different type of products, hence respective MNO can be repeated.)
5. (a)-(ii)- (ANSWER) Degree=No.
of columns= 4 , Cardinality=No. of rows
= 5
5.(b)-(i)-SELECT TITLE FROM
SUBJECT WHERE MARKS_PRAC=0;
(II) SELECT COUNT(TCODE),SUB_CODE
FROM TEACHER GROUP BY SUB_CODE;
(III) SELECT NAME FROM TEACHER ORDER BY SUB_CODE;
(IV) SELECT CODE , TITLE, (MARKS_THEORY+MARKS_PRAC) AS “
TOTAL MARKS” FROM SUBJECT ;
5.(C) SELECT
SUBJECT.TITLE , TEACHER.NAME
FROM SUBJECT , TEACHER where SUBJECT.CODE=TEACHER.SUB_CODE ;
5.(d)-(i) output :
100
70
(ii)output :
4 Shabnam
5 Rashika
6 Vidushi
7 Yash
5.(e) In subject table “ code” can be made PRIMARY KEY. In TEACHER table “TCode” can be made PRIMARY KEY
7.(a) ANS—RADIO WAVE
7.(b) POP3 protocol is used to receive emails.
7.(c)COOKIE S -Information sent by webserver to the web
browser.
7.(d) client-side script
7.(e) Free Software: The S/W’s is freely
accessible and can be freely used changed improved copied and distributed by
all and payments are needed to make for free S/W.
Freeware: Freeware
are the software freely available , which permit redistribution but not
modification (and their source code is not available). Freeware is distributed
in Binary Form (ready to run) without any licensing fees.
