Important Questions for Class 12 Computer Science (C++)

Previous years Examination Questions
2 Marks Questions

Question 1:
What is the relationship between a class and an object? Illustrate with a suitable example. Delhi 2013C
Аnswers:
Class
• It is a user-defined data type.
• It is a logical framework that combines data and function into a single unit.
e.g

class GABS 
{
int a,b; 
public:
void set() 
{
a=10; 
b=20;
}
void show()
{
cout<<"Value of a and b is"<<a<<b<<endl;
};

Object
• It is an instance of a class.
• It is a physical entity that means it occupies space in a memory. It’s used to access members of the class.
e.g. Suppose “GABS” is the name of the class.
GABS G1, G2;
G1.show( );
Both G1 and G2 are the objects of the class “GABS”

Question 2:
Rewrite the following program after removing the syntactical errors (if any). Underline each correction. Delhi 2012

#include<iostream.h> 
class Book 
{
long Bld.Qty; 
public:
void Purchase()
{
cin>>BId<<Qty;
}
void Sale 
{
cout<<setw(5)<<BId<<"o1d:”<<Qty<<endl;
cout<<"New:"<<—Qty<<endl;
}
};
void main()
{
Book B;
B.Purchase();
Sale();
B.Sale();
}

Аnswers:

#include<iostream.h>
#include<iomanip.h> 
class Book
{
long Bid, Qty; 
pub!ic:
void Purchase()
{
cin>>BId>>Qty;
}
void Sale()
{
cout<<setw(5)<<BId<<"o1d:"<<Qty<<endl; 
cout<<"New:"<<--Qty<<endl;
}
};
void main()
{
Book B;
B.Purchase();
B.Sale(); 
B.Sale();
}

Question 3:
Rewrite the following program after removing the syntactical errors (if any). Underline each correction. Delhi 2012

#include<iostream.h> 
class Item 
{
long IId, Qty; 
public:
void Purchase 
{
cin>>IId>>Qty;
}
void Sale()
{
cout<<setw(5)<<IId<<”old:"<<Qty<<endl;
cout<<"New: "<<--Qty<<endl;
}
};
void main()
{
Item I;
Purchase():
I.Sale();
I.Sale();
}

Аnswers:

#include<iostream.h> 
#include<iomanip.h> 
class Item
{
long lid,Qty; 
public:
void Purchase()
{
cin>>IId>>Qty;
}
void Sale()
{
cout<<setw(5)<<IId<<"01d:"<<Qty<<endl;
cout<<"New:"<<--Qty<<endl;
}
};
void main()
{
Item I;
I.Purchase();
I.Sale();
I.Sale();
}

Question 4:
Rewrite the following program after removing the syntactical error(s) (if any). Underline each correction. Delhi 2012C

#include<iostream.h>
#include<stdio.h>
Class OFFER 
{
int OfferId; 
char Description[80]: 
void Show 
{
cout<<offerId<<" : ”<<Description<<endl;
}
public:
void Enter 
{
cin>>offerId; 
gets>>Description;
}
};
void main()
{
OFFER Obj;
Obj.Enter();
Obj.Show();
}

Аnswers:

#include<iostream.h> 
#include<stdio.h> 
class OFFER
{
int OfferId; 
char Description[80]; 
void Show()
{
cout<<offerld<<":"<<Description<<endl; 
}
public:
void Enter()
{ 
cin>>offerId; 
gets(Description):
}
};
void main()
{
OFFER Obj;
Obj.Enter();
//Obi.Show();
//Show()cannot be called because
//it is a private member
}

Question 5:
What is the difference between members in private visibility mode and the members in public visibility mode inside a class? Also give a suitable C++ code to illustrate both. Delhi 2012
or
Differentiate between public and private visibility modes in context of object oriented programming using a suitable example. Delhi 2011
Аnswers:
A member declared as private remains hidden from outside world and it can only be accessed by the member function of the class in which it is declared. A member declared as public is made available to the outside world. That is , it can be accessed by any function, any expression in the program but only by using an object of the same class type.
e.g-

class A 
{
private:
int x;
void show(); 
public: 
int y;
void get();
};

The members x and show( ) are private and these are not accessible outside the class where the members y and get( ) are public so these are accessible outside the class.

Question 6:
When is public visibility of a mode applied to members of a class? Also give an example to illustrate. Delhi 2011C
Аnswers:
When we need to access the members from out side the class then we apply public mode preceding any members.
e.g.

#include<iostream.h> 
class ABC 
{
public: 
int b; 
void show()
{
cout<<"b ="<<b;
}
};
void main()
{
ABC x; 
x.b=20; 
x.show();
}

Question 7:
Rewrite the following C++ program code after removing the syntax error(s) (if any). Underline each correction.
All India 2010

include<iostream.h>
class FLIGHT 
{
long FlightCode;
char Description[25]; 
public
void Addlnfo()
{
cin>>FlightCode; 
gets(Description);
}
void ShowInfo()
{
cout<<FlightCode«":" <<Description<<endl;
}
};
void main()
{
FLIGHT F;
Addlnfo.F();
Showlnfo.F();
}

Аnswers:

# include<iostream.h>
#include<stdio.h>
class FLIGHT 
{
long FlightCode; 
char Description[25]; 
public:
void Addlnfo()
{
cin>>FlightCode; 
gets(Description);
}
void Showlnfo()
(
cout<<FlightCode<<":"<<Description<<endl;
}
};
void main()
{
FLIGHT F;
F.Addlnfo();
F.ShowInfo();
}

Question 8:
Rewrite the following C++ program code after removing the syntax error(s) (if any). Underline each correction.
Delhi 2010

#include<iostream.h> 
class TRAIN 
{
long TrainNo;
char Description[25];
public
void Entry()
{
cin>>TrainNo; 
gets(Description);
}
void Display()
{
cout<<TrainNo<<":"<<Description<<endl;
}
};
void main( )
{
TRAIN T;
Entry. T();
Display.T();
}

Аnswers:

#include<iostream.h> 
#include<stdio.h> 
class TRAIN 
{
long TrainNo;
char Description[25];
public:
void Entry()
{
cin>>TrainNo;
gets(Description);
}
void Display()
{
cout<<TrainNo<<" : "<<Description<<endl;
}
};
void main()
{
TRAIN T;
T.Entry();
T.Display();
}

Question 9:
Rewrite the following program after removing the syntactical error(s) (if any) Underline each correction. Delhi 2009C

#include<iostream.h>
class Transport 
{
char Model[20]; 
char Name[20]; 
void Get()
{
gets(Model); 
gets(Name);
}
void Show()
{
cout<<Model<<endl; 
puts(Name);
}
};
void main( )
{
Transport T;
T.Get();
Show();
}

Аnswers:

#include<iostream.h> 
#include<stdio.h> 
class Transport 
{
char Model[20]; 
char Name[20]; 
public: 
void Get() 
{
gets(Model); 
gets(Name);
}
void Show() 
{
cout<<Model<<endl; 
puts(Name);
}
};
void main()
{
Transport T:
T.Get();
T.Show();
}

4-5 Marks Questions

Question 10:
Write the definition of a class BOX in C++ with the following description: All India 2017

Аnswer:

class Box 
{
int BoxNumber; 
float Side, Area; 
void ExecArea()
{
Area = Side*Side;
}
public:
void GetBox()
{
cout<<"Enter the values of BoxNumber and Side”; 
cin>>BoxNumber; 
cin>>Side;
ExecArea(); 
}
void ShowBox()
{
cout<<"BoxNumber:"<<BoxNumber<<endl; 
cout<<”Side:"<<Side<<endl: 
cout<<”Area:"<<Area;
}

Question 11:
Write the definition of a class METROPOLIS in C++ with following description: Delhi 2016

Аnswer:

class METROPOLIS 
{
int MCode; 
char MName[20]; 
long int MPop; 
float Area, PopDens; 
void CalDen()
{
PopDens = MPop/Area;
}
public:
void Enter()
{
cout<<"\nEnter the code";
cin>>MCode;
cout<<"\nEnter the name"; 
gets(MName);
cout<<"\n Enter the population"; 
cin>>MPop;
cout<<"\n Enter the area coverage";
cin>>Area;
CalDen();
}
void ViewALL() 
{
cout<<"\nCode: "<<MCode; 
cout<<"\nName: "<MName; 
cout<<"\nPopulation:"<<MPop; 
cout<<"\nArea Coverage : "<<Area ; 
cout<<"\nPopulation Density :"<<PopDens; 
if(PopDens>12000)cout<<"Highly Populated Area";
}
};

Question 12:
Write the definition of a class CITY in C++ with following description: All India 2016

Аnswer:

class CITY 
{
int Ccode;
char CName[20];
long int Pop; 
float KM, Density; 
void DenCal()
{
Density = Pop/KM;
}
public :
void Record()
{
cout<<"\nEnter the city code"
cin<<Ccode;
cout<<"\nEnter the city name"
gets(CName);
cout<<"\nEnter city’s population"
cin>>Pop;
cout<<"\nEnter the Area coverage by city";
cin>>KM;
DenCal ();
}
void View()
{
cout<<"\nCity code:"<<Ccode; 
cout<<"\nCity name:"<<CName; 
cout<<"\nPopul at ion:"<<Pop; 
cout<<"\nArea coverage:"<<KM;
cout<<"\nPopul ation density:"<<Density; 
if(Density>10000) 
cout<<"Highly Populated City"; 
}
};

Question 13:
Write the definition of a class PIC in C++ with following description Delhi 2015

Аnswer:

class PIC 
{
int Pno;
char Category[20]; 
char Location[20]; 
void FixLocation()
{
if(strcmp(Category,"Antique”)==0) 
strcpy(Location,"Ustad Khan"); 
else if(strcmp(Category,"Modern" )==0)
strcpy(Location,"Jim Plaq”); 
else if(strcmp(Category,”Classic”)==0) 
strcpy(Location,"Amina");
}
public:
void Enter() 
{
cout<<"\nEnter the picture number";
cin>>Pno;
cout<<"\nEnter the category"; gets(Category);
FixLocation(); 
}
void SeeAll() 
{
cout<<"\nPicture number:"<<Pno; 
cout<<"\nCategory: "<<Category; 
cout<<"\nLocation:"<<Location; 
}
};

Question 14:
Write the definition of a class Photo in C++ with following description: All Indio 2015

Аnswer:

class Photo 
{
int Pno;
char Category[20]; 
char Exhibit[20]; 
void FixExhibit()
{ 
if(strcmp(Category,"Antique")== 0) 
strcpy(Exhibit, "Zaveri"); 
else if(strcmp(Category,"Modem") == 0) 
strcpy(Exhibit, "Johnsen"); 
else if(strcmp(Category,"Classic") == 0) 
strcpy(Exhibit, "Terenida”);
}
public:
void Register()
{
cout<<"\nEnter the photo number";
cin>>Pno;
cout<<"\nEnter the category"; 
gets(Category);
FixExhibit();
}
void ViewAll()
{
cout<<"\nPhoto number :"<<Pno; 
cout<<"\nCategory:"<<Category; 
cout<<"\nExhibit:”<<Exhibit;
}
};

Question 15:
Write the definition of a class STAFF in C++ with following description: All India 20isc

Public Members

Enroll( ) //A function to allow user to enter values
//SID, Type, Name and call
//AssignPay( ) function
SeeData( ) //A function to display all the data members

Аnswer:

class STAFF 
{
long int SID; 
char Type; 
float Pay; 
char Name[30]; 
void AssignPay()
{
if(Type == 'D')
Pay = 95000; 
else if(Type == 'M')
Pay = 75000; 
else if (Type == 'E')
Pay = 60000; 
else if(Type == 'S')
Pay = 45000;
}
public:
void Enroll()
{
cout<<”Enter the values of staff ID, Type, Name"; 
cin>>SID; 
cin>>Type; 
gets(Name);
AssignPay();
}
void seeData()
{
cout<<SID<<Type<<Name<<Pay;
}
};

Question 16:
Define a class Seminar with the following specification private members: Delhi 2013C
Seminarld long
Topic string of 20 characters
VenueLocation string of 20 characters
Fee float
CalcFee( ) function to calculate Fee depending on VenueLocation

Venue Location	Fee
Outdoor	5000
Indoor Non-AC	6500
Indoor AC	7500

Public members
Register( ) function to accept values for Seminarld, Topic, VenueLocation and call CalcFee( ) to calculate Fee.
ViewSeminarf( ) function to display all the data members on the screen.

Аnswer:

class Seminar 
{
long SeminarId;
char Topic[20]. VenueLocation[20]; 
float Fee; 
void CalcFee()
{
if(strcmp(VenueFocation,"Outdoor")==0)
Fee=5000;
else if(strcmp(Venuetocation,"Indoor Non-AC")==0) 
Fee=6500;
else if(strcmp(VenueFocation,"Indoor AC")==0)
Fee=7500;
}
public:
void Register()
{
cout<<"Enter Seminar Id"; 
cin>>SeminarId; 
cout<<"Enter Topic"; 
gets(Topic);
cout<<"Enter Venue Location";
gets(VenueLocation);
CalcFee(); 
}
void ViewSeminar()
{ 
cout<<"SeminarId:"<<SeminarId<<endl; 
cout<<"Topic: "<<Topic<<endl; 
cout<<"Venue Location;"<<VenueFocation<<endl; 
cout<<"Fee is:"<<Fee;
}
};

Question 17:
Define a class RESTRA in C++ with following description: Delhi 2012
Private members

FoodCode of type int
Food of type string
FType of type string
Sticker of type string
A member function GetStickerf( ) to assign the following values for Food Sticker as per the given FType

FType Sticker
Vegetarian GREEN
Contains Egg YELLOW
Non-Vegetarian RED

Public members

A function GetFood( ) to allow user to enter values for FoodCode, Food, FType and call function GetSticker( ) to assign Sticker.
A function ShowFoodf( ) to allow user to view the content of all the data members.

Аnswer:

class RESTRA 
{
int FoodCode;
char Food[30], FType[20],Sticker[20];
void GetSticker()
{
if(strcmp(FType,"Vegetarian”)==0) 
strcpy(Sticker,"GREEN"); 
else if(strcmp(FType,"Contains Egg")==0)
strcpy(Sticker,"YELLOW"); 
else if(strcmpCFType,"Non-Vegetarian")==0) 
strcpy(Sticker,"RED”); 
}
public:
void GetFood() 
{
cout<<"Enter FoodCode, Food, Food Type";
cin>>FoodCode; 
gets(Food); 
gets(FType);
GetSticker();
}
void ShowFood()
{ 
cout<<"Entered values of FoodCode, Food, FoodType,Sticker";
cout<<FoodCode<<Food<<FType<<Sticker;
}
};

Question 18:
Define a class SUPPLY in C++ with following description: All Indio 2012
Private members

Code of type int
FoodName of type string
Sticker of type string
FoodType of type string
A member function GetTypef ( ) to assign the following values for FoodType as per the given Sticker

Sticker FoodType
GREEN Vegetarian
YELLOW Contains Egg
RED Non-Vegetarian
Public members

A function FoodIn( ) to allow user to enter values for Code, FoodName, Sticker and call function GetType( ) to assign respective FoodType.
A function FoodOut( ) to allow user to view the content of all the data members.

Аnswer:

class SUPPLY 
{
int Code;
char FoodName[30],Sticker[30]; 
char FoodType[20]; 
void GetType()
{
if(strcmp(Sticker, "GREEN”)==0) 
strcpy(FoodType,"Vegetarian" ); 
else if(strcmp(Sticker,"YELLOW")==0) 
strcpy(FoodType,"Contains Egg"); 
else if(strcmp(Sticker,"RED")==0) 
strcpy(FoodType,"Non -Vegeta rian"); 
}
public:
void FoodIn()
{
cout<<"Enter Code, FoodName, Sticker";
cin>>Code;
gets(FoodName); 
gets(Sticker);
GetType(); 
}
void Food0ut()
{
cout<<"Code,FoodName,Sticker,FoodType are"; 
cout<<Code<<FoodName<<Sticker<<FoodType;
}
};

Question 19:
Define a class Candidate in C++with following description: Delhi 2o11
Private members

A data member RNo (Registration Number) of type long
A data member Name of type string
A data member Score of type float
A data member Remarks of type string
A member function AssignRem( ) to assign the remarks as per the score obtained by a candidate.
Score range and the respective remarks are shown as follow:

Score Remarks
>=50 Selected
less than 50 Not Selected
Public members

A function ENTER( ) to .allow user to enter values for RNo, Name, .Score and call function AssignRem( ) to assign Remarks.
A function DISPLAY( ) to allow user to view the content of all data members.

Аnswer:

class Candidate 
{
long RNo; 
char Name[40]; 
float Score; 
char Remarks[20]; 
void AssignRem()
{
if(Score>=50)
strcpy(Remarks,"Selected"); 
else
strcpy(Remarks,"Not Selected");
}
public: 
void ENTER()
{
cout<<"Enter the values for Rno,Name,Score”;
cin>>RNo; 
gets(Name); 
cin>>Score;
AssignRem(); 
}
void DISPLAY()
{
cout<<RNo<<Name<<Score<<Remarks; 
}
};

Question 20:
Define a class Applicant in C++ with following description: All IndiA 2011
Private members

A data member ANo (Admission Number) of type long
A data member Name of type string
A data member Agg (Aggregate Marks) of type float
A data member Grade of type char
A member function GradeMe( ) to find the grade as per the aggregate marks obtained by a student. Equivalent aggregate marks range and the respective grades are shown as follow:

Aggregate marks Grade
>=80 A
less than 80 and >=65 B
less than 65 and >=50 C
less than 50 D
Public members

A function ENTER( ) to allow user to enter values for ANo, Name, Agg and call function GradeMe( ) to find the Grade.
A function RESULT( ) to allow user to view the content of all data members.

Аnswer:

class Applicant
{
long ANo; 
char Name[40]; 
float Agg; 
char Grade; 
void GradeMe()
{
if(Agg>=80) 
Grade='A';
else if(Agg<80 && Agg>=65) 
Grade='B';
else if(Agg<65 && Agg>=50) 
Grade='C'; 
else
Grade='D';
public: 
void ENTER()
{
cout<<"Enter the values for Ano.Name.Agg"
cin>>ANo; 
gets(Name); 
cin>>Agg;
GradeMe();
}
void RESULT()
{
cout<<ANo<<Name<<Agg<<Grade;
}
};

Question 21:
Define a class ITEM in C++ with the following specification: Delhi 2010
Private members

Code of type integer (Item Code)
Iname of type string (Item Name)
Price of type float(Price of each item)
Qty of type integer(Quantity of item stock)
Offer of type float(Offer percentage on the item)
A member function GetOffer( ) to calculate offer percentage as follows:

If Qty <=50 Offer is 0
If 50<Qtv<=l 00 Offer is 5
If Qty >100 Offer is 10
Public members

A function GetStock( ) to allow user to enter values for Code, Iname, Price, Qty and call function GetOffer( ) to calculate offer.
A function ShowItem( ) to allow user to view the content of all data members.

Аnswer:

class ITEM
{
int Code;
char Iname[20]: 
float Price; 
int Qty; 
float Offer; 
void GetOffer()
{
if(Qty<=50) 
Offer=0;
else if(Qty<=100) 
Offer=5; 
else
Offer=10;
}
public:
void GetStock()
{
cout<<"Enter the values for code, Item name, Price, Quantity";
cin>>Code; 
gets(Iname); 
cin>>Price>>Qty;
GetOffer();
}
void ShowItem()
{
cout<<Code<<Iname<<Price<<Qty<<Offer;
}
};

Question 22:
Define a class STOCK in C++ with the following specification: All India 2010
Private members

ICode of type integer (Item Code)
Item of type string (Item Name)
Price of type float(Price of each item)
Qty of type integer(Quantity in stock)
Discount of type float(Discount percentage on the item)
A member function FindDisc( ) to calculate discount percentage as follows:

If Qty <=50 Discount is 0
If 50<Qty<=100 Discount is 5
If Qty >100 Discount is 10 Public members

A function Buy( ) to allow user to enter values for ICode, Item, Price, Qty and call function FindDisc( ) to calculate discount.
A function ShowAll( ) to allow user to view the content of all data members.

Аnswer:

class STOCK 
{
int ICode; 
char Item[20]: 
float Price: 
int Qty; 
float Discount: 
void FindDisc():
{
if(Qty<=50)
Discount=0; 
else if(Qty<=100) 
Discount=5; 
else
Discount=10;
}
public: 
void Buy()
{
cout<<"Enter the values for Icode,Item,Price,Qty"; 
cin>>ICode; 
gets(Item); 
cin>>Price>>Qty;
FindDisc();
}
void ShowAll()
{
cout<<ICode<<Item<<Price<<Qty<<Discount;
}
};

Question 23:
Define a class RESORT in C++ with the following specification: Delhi 2009
Private members

Rno – Data member to store room number
Name – Data member to store customer name
Charges – Data member to store per day charges
Days – Data member to store number of days of stay
COMPUTEO – Function to calculate and return amount as days*charges and if the value of days *charges is more than 11000, then as 1.02*Days *Charges

Public members

Getinfo( ) Function tfo enter the content Rno, Name, Charges and Days
Dispinfo( ) Function to display Rno, Name, Charges, Days and Amount (amount to be displayed by calling function COMPUTE( ))

Аnswer:

class RESORT 
{
int Rno; 
char Name[30]; 
float Charges; 
int Days ; 
float COMPUTE()
{
float temp=Days*Charges; 
if(temp>11000) 
return(1.02*temp);
return temp; 
}
public:
void Getinfo()
{
cout<<"enter the room number:"; 
cin>>No;
cout<<"enter the customer name:"; 
gets(Name);
cout<<”enter the room charges per day";
cin>>Charges;
cout<<"enter number of days stayed by customer:"; 
cin>>Days:
}
void Dispinfo()
{
cout<<"Room number:"<<Rno; 
cout<<"Customer Name:"; 
puts(Name) ;
cout<<"Charges per day:"<<Charges; 
cout<<"Number of days stayed by customer:"<<Days; 
cout<<"Total charges of customer: "<<COMPUTE();
}
};

Question 24:
Define a class HOTEL in C++ with the following specification: All IndiA 2009
Private members

Rno Data member to store room number
Name Data member to store customer name
Tariff Data member to store per day charges
NOD Data member to store number of days of stay
CALC( ) Function to calculate and return amount as NOD*Tariff and if the value of NOD*Tariff is more than 10000, then as 1.05 NOD *charges

Public members

Checkin( ) Function to enter the content Rno, Name, Tariff and NOD
Checkout( ) Function to display Rno, Name, Tariff, NOD and Amount (amount to be displayed by calling function
CALC( ))

Аnswer:

class HOTEL 
{
int Rno,NOD; 
char Name[30]; 
float Tariff; 
float CALC()
{
float temp=NOD*Tariff; 
if(temp>10000) 
return(1.05*temp); 
return temp;
} 
public:
void Check In()
{
cout«"Enter the room number:";
cin>>Rno;
cout<<"Enter the customer name:";
gets(Name);
cout<<"Enter the room charges per day";
cin>>Tariff ;
cout<<"Enter number of days stayed by customer:"; 
cin>>NOD;
}
void Checkout()
{
cout<<"Room number:"<<Rno; 
cout<<"Customer Name:"; 
puts(Name); 
cout<<"Charges per day:"<<Tariff; 
cout<<"Number of days stayed by customer:"<<NOD; 
cout<<"Total charges of customer:"<<CALC();
}
};

Important Questions for Class 12 Computer Science (C++) – Classes and Objects

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