Attempt this MCQ. I will post its answers after 2 days
Kulachi Hansraj Model School
Multiple Choice Questioner
(General Concepts, Header Files, File Handling)
Class XII
Time : 15 min. M.Marks : 30
1. When working with character arrays, always reserve enough array elements to hold the string AND its null-terminating character (\0).
[a] True [b] False
2. In C++, 14 % 4 =
[a] 1 [b] 2 [c] 3 [d] 4
3. Variables that are declared, but not initialized, contain
[a] blank spaces [b] zeros [c] "garbage" values [d] nothing - they are empty
4. Array indexing always starts with the number
[a] 0 [b] 1 [c] 2 [d] \0
5. A character variable may contain up to seven letters.
[a] True [b] False
6. All strings end with a null zero in memory.
[a] True [b] False
7. The name of a variable is known as its
[a] identifier [b] constant
[c] data type [d] base
8. In C++, the % refers to
[a] percentages [b] modulus operator
[c] division [d] data storage
9. A variable is given a value through
[a] osmosis [b] the cout statement
[c] the
10. Variable names may begin with a number.
[a] True [b] False
11. When a data type must contain decimal numbers, assign the type
[a] int [b] char [c] double [d] long int
12. Mathematicians and computers interpret the equal sign (=) in the same way.
[a] True [b] False
13. setprecision requires the header file
[a] stdlib.h [b] iomanip.h [c] console.h [d] conio.h
14. The following statement is valid. double price = 7,450.98;
[a] True [b] False
15. All variables must be declared before they can be used.
[a] True [b] False
16. Character literals always have a length of one.
[a] True [b] False
17. If char catname[15]; , which of the following is valid?
[a] catname[15] = "Millie"; [b] catname = "Millie";
[c] catname[ ] = "Millie"; [d] none are valid
18. Which type of data file is analogous to an audio cassette tape?
[a] random access file [b] sequential access file
[c] binary file [d] source code file
19. Which of the following header files is required for creating and reading data files?
[a] ofstream.h [b] fstream.h
[c] ifstream.h [d] console.h
20. If you create a file with the same name as an existing file, you will be prompted to rename your new file.
[a] True [b] False
21. In the code fout.open("scores.dat", ios::out);
[a] ios::out is the stream operation mode.
[b] fout is the header file reference.
[c] ios::out is the stream variable name..
[d] fout is the name of the file.
22. A text editor can be used to view, or create, a file.
[a] True [b] False
23. What header file contains C++ file I/O instructions?
[a] iostream.h [b] fstream.h
[c] infstream.h [d] outstream.h
24. ifstream fin; would be used when
[a] creating a file [b] reading a file
[c] appending a file [d] removing a file
25. eof( ) is the function used for
[a] asserting no errors in a file [b] appending data to a file
[c] counting the amount of data in a file [d] checking for end of file
26. If a file you are opening for appending does not exist, the operating system will detect the missing file and terminate the operation.
[a] True [b] False
27. It is possible to open several files for access at the same time.
[a] True [b] False
28. Which of the following is not a valid ofstream argument?
[a] ios::app [b] ios::trunc
[c] ios::noreplace [d] ios::create
29. What does ios::ate mean as an argument to ofstream?
[a] Open file, but do not create. [b]Open file, create.
[c] Open file for read access only.[d]Open file, set the position to the end.
30. How would you output to an open file named a_file?
[a] a_file.out("Output"); [b] a_file="Output";
[c] a_file<<"Output"; [d]a_file.printf("Output");
Struct NODE
{
int Data;
NODE *Next;
};
class Queue
{
NODE *Rear,*Front;
public:
Queue(){Rear=NULL;Front=NULL;}
Void Qinsert();
Void Qdelete();
Void Qdisplay();
~Queue();
};
_______________________________________________________________
void Queue::Qinsert()
{
NODE *Temp;
Temp=new NODE;
Cout<<”Data:”;
Cin>>Temp->Data;
Temp->Next=NULL;
If (Rear==NULL)
{
Rear=Temp;
Front=Temp;
}
else
{
Rear->Next=Temp;
Rear=Temp;
}
}
_______________________________________________________________
void Queue::Qdelete()
{
if (Front!=NULL)
{
NODE *Temp=Front;
Cout<
Front=Front->Next;
Delete Temp;
If (Front==NULL) Rear=NULL;
else
cout<<”Queue Empty..”;
}
_______________________________________________________________
void Queue::Qdisplay()
{
NODE *Temp=Front;
While(Temp!=NULL)
{
cout<
Temp=Temp->Next;
}
_______________________________________________________________
void Queue::~Queue()//Destructer Function
{
while (Front!=NULL)
{
NODE *Temp=Front;
Front=Front->Next;
delete Temp;
}
}
_______________________________________________________________
void main()
{
Queue QU; char Ch;
do
{
}while (Ch!=’Q’);
}
_______________________________________________________________
};
class LStack
{
NODE *Top;
Public:
LStack(){Top=NULL;}
void Push();
void Pop();
void show_stack();
~LStack();
};
void LStack::Push()
{
NODE * ptr;
ptr=new NODE;
cout<<”Data:”;
cin>>ptr->Data;
ptr->link=Top;
Top=ptr;
}
void LStack::Pop()
{
if (Top!=NULL)
{
NODE *Temp=Top;
Cout<
Top=Top->link;
delete Temp;
}
else
cout<<”Stack Empty..”;
}
void LStack::show_stack()
{
NODE *Temp=Top;
while(Temp!=NULL)
{
cout<
Temp=Temp->link;
}
}
void LStack::~LStack() //Destructer Function
{
while (Top!=NULL)
{
NODE *Temp=Top;
Top=Top->Next;
delete Temp;
}
}
void main()
{
Stack ST; char Ch;
do
{
cout<<”P/O/D/Q”;cin>>Ch;
switch (Ch)
{
case ’P’:ST.Push();break;
case ’O’:ST.Pop();break;
case ’D’:ST.show_stack();
}
}
while (Ch!=’Q’);
} // Destructor function will be called
// automatically when the scope of the
// object gets over
Tomorrow I will be sharing with you the concepts related to pointers and Dynamic memory allocation ......
There are 3 important places where a copy constructor is called.
If a copy constructor is not defined in a class, the compiler itself defines one. This will ensure a shallow copy. If the class does not have pointer variables with dynamically allocated memory, then one need not worry about defining a copy constructor. It can be left to the compiler's discretion.
But if the class has pointer variables and has some dynamic memory allocations, then it is a must to have a copy constructor. (Find its example in BLUE colour)
For ex:
class A //Without copy constructor
{ private:
int x;
public:
A() {A = 10;}
~A() { }
};
class B //************** With copy constructor ************
{
private:
int month;
public:
B( int y) //********* Parameterized constructor ***********
{
month = y;
}
~B( )
{
cout << "destructor function invoked"; }
B( B &b) //*************** Copy constructor *************
};
class B //With copy constructor
{
private:
char *name;
public:
B()
{
name = new char[20];
}
~B()
{
delete name[];
}
//Copy constructor
B(B &b)
{
name = new char[20];
strcpy(name, b.name);
}
};
Example : When an object is created from another object of the same type
class A
{ int a;
public:
A(int x )
{ cout <<"Constructor invoked ..."; a=x; } }Obj1(23); A Obj2=Obj1; }
