When the base class is publicly inherited, public members of the base class become …………. of the derived class. private members protected members Public members Not inherited
Public members
In ……………….. inheritance, the base classes are constructed in the order in which they appear in the deceleration of the derived class. multipath multiple multilevel hierarchical
multiple
If 2 classes derive one base class and redefine a function of base class, also overload some operators inside class body. Among these two things of function and operator overloading, where is polymorphism used? Function overloading only Operator overloading only Both of these are using polymorphism Either function overloading or operator overloading because polymorphism can be applied only once in a program
Either function overloading or operator overloading because polymorphism can be applied only once in a program
In case of using abstract class or function overloading, which function is supposed to be called first? Local function Function with highest priority in compiler Global function Function with lowest priority because it might have been halted since long time, because of low priority
Function with highest priority in compiler
Quiz 2
The output of following program
#include<iostream>
using namespace std;
class Base
{
public:
virtual void show() { cout<<" In Base n"; }
};
class Derived: public Base
{
public:
void show() { cout<<"In Derived n"; }
};
int main(void)
{
Base *bp, b;
Derived d;
bp = &d;
bp->show();
bp = &b;
bp->show();
return 0;
}
a) In Base In Base b) In Base In Derived c) In Derived In Derived d) In Derived In Base
d) In Derived In Base
……………. binding means that an object is bound to its function call at compile time. late static dynamic fixed
static
A …………………. refers to an object that that currently invokes a member function. void pointers null pointers this pointer base pointer
this pointer
Which of the following is true about pure virtual functions? 1) Their implementation is not provided in a class where they are declared. 2) If a class has a pure virtual function, then the class becomes abstract class and an instance of this class cannot be created. Both 1 and 2 Only 1 Only 2 Neither 1 nor 2
*pending
Surprise Test
State whether the following statements about inheritance are True or False. i) A public member of a class can be accessed by its own objects using the dot operator. ii) While inheriting, the private members of the base class will never become members of its derived class. True, False False, True True, True False, False
True, True
A derived class with only one base class is called …………… inheritance. single multiple multilevel hierarchical
single
A member declared as ………….. is accessible by the member functions within its class and any class immediately derived from it. protected private public friend
The friend functions and the member functions of a friend class can directly access the ………………. data. private and protected private and public protected and public private, protected and public
private and protected
False statements about function overloading is Defining multiple functions with same name in a class is called function overloading Overloaded function must differ in their order and types of arguments. Overloaded functions should be preceded with virtual keyword No statement is false
Overloaded functions should be preceded with virtual keyword
Compile time polymorphism in C++ language are Operator overloading Function overloading Function overriding A & B
A & B
Which among the following can’t be used for polymorphism? Static member functions Member functions overloading Predefined operator overloading Constructor overloading
Static member functions
Run time polymorphism is achieved only when a ……………….. Is accessed through a pointer to the base class. static function Real function Member function Virtual function
Virtual function
The pointer to a function is known as …………………. function. forward pointer callback backward
callback
When VTABLE (Virtual table) get created for a class? Every class by default has virtual table When a Class Overrides the function of Base class When a class contains at least one virtual function. When a class is derived from a base class.
When a class contains at least one virtual function.
Which concept is not available in C++? Virtual constructor Virtual destructor Virtual function Virtual Table
Virtual constructor
The output of following program is
#include<iostream>
using namespace std;
class Base
{
public:
virtual void show() { cout<<" In Base n"; }
};
class Derived: public Base
{
public:
void show() { cout<<"In Derived n"; }
};
int main(void)
{
Base *bp, b;
Derived d;
bp = &d;
bp->show();
bp = &b;
bp->show();
return 0;
}
a) In Base In Base b) In Base In Derived c) In Derived In Derived d) In Derived In Base
d) In Derived In Base
Practical
Pre
When the inheritance is private, the private methods in base class are __ in the derived class (in C++) Inaccessible Accessible Protected Public
Inaccessible
What is meant by multiple inheritance? Deriving a base class from derived class Deriving a derived class from base class Deriving a derived class from more than one base class None of the mentioned
Deriving a derived class from more than one base class
Can we pass parameters to base class constructor though derived class or derived class constructor? Yes No May Be Can’t Say
Yes
Which symbol is used to create multiple inheritance? Dot Comma Dollar None of the above
Comma
Functions that can be inherited from base class in C++ program Constructor Destructor Static function None
Which of the following shows multiple inheritances? A->B->C A->B; A->C A,B->C B->A
A,B->C
How access specifiers in Class helps in Abstraction? They does not helps in any way They allows us to show only required things to outer world They help in keeping things together Abstraction concept is not used in classes
They allows us to show only required things to outer world
Out of the following, which is not a member of the class? Static function Friend function Constant function Virtual function
Friend function
What is the other name used for functions inside a class? Member variables Member functions Class functions Class variables
Member functions
Which of the following approach is used by C++? Top-down Bottom-up Left-right Right-left
Bottom-up
The __, also known as the address operator, returns the memory address of a variable. asterisk (* ) ampersand ( & ) percent sign ( % ) exclamation point ( ! )
ampersand ( & )
A function may return a pointer but the programmer must ensure that the pointer still points to a valid object after the function ends has not been assigned an address was received as a parameter by the function has not previously been returned by another function
still points to a valid object after the function ends
What does the following statement do? double *num2; Declares a double variable named num2 Declares and initializes a pointer variable named num2 Initializes a pointer variable named num2 Declares a pointer variable named num2
Declares a pointer variable named num2
Use the delete operator only on pointers that were never used not correctly initialized created with the new operator dereferenced inappropriately
created with the new operator
In C++, the __ keyword was introduced to represent address 0. nullptr NULL weak_ptr shared_ptr
nullptr
Post
Which among the following is best to define hierarchical inheritance? More than one classes being derived from one class More than 2 classes being derived from single base class At most 2 classes being derived from single base class At most 1 class derived from another class
More than one classes being derived from one class
Which class uses hierarchical inheritance in following code?
class A
{
int a;
};
class B:class A
{
int b;
};
class C:class A,class B
{
int c;
};
class D:class A
{
int d;
};
Class A, B, C Class B, C, D Class A, C, D Class A, D, B
Class A, D, B
Which among the following is correct for following code?
#include <iostream>
using namespace std;
class A{
public: int a=10;
void disp()
{
cout<<"in base class";
}
};
class B:public A
{
public: void dis()
{
cout<<a;
}
};
int main()
{
B b;
b.disp();
return 0;
}
Compile time error Runtime error Program runs and o/p is 10 Program runs and o/p is “in base class”
Hierarchical inheritance can be a subset of _____ Hybrid inheritance Multiple inheritance Single level inheritance Multilevel inheritance
Hybrid inheritance
What does polymorphism in OOPs mean? Concept of allowing overriding of functions Concept of hiding data Concept of keeping things in different modules/files Concept of wrapping things into a single unit
Concept of allowing overriding of functions
Which of the following explains Polymorphism? a) int func(int, int); float func1(float, float); b) int func(int); int func(int); c) int func(float); int func(int, int, char); d) int func(); int new_func();
c) int func(float); int func(int, int, char);
Which of the following feature of OOPs is not used in the following C++ code?
Which of the following feature of OOPs is not used in the following C++ code?
class A
{
int i;
public:
void print(){cout<<"hello"<<i;}
}
class B:public A
{
int j;
public:
void assign(int a)
{
j = a;
}
}
How run-time polymorphisms are implemented in C++? Using Inheritance Using Virtual functions Using Templates Using Inheritance and Virtual functions
Using Inheritance and Virtual functions
How compile-time polymorphisms are implemented in C++? Using Inheritance Using Virtual functions Using operator overloading Using Inheritance and Virtual functions
Using operator overloading
Assuming ptr is a pointer variable, what will the following statement output? cout<< ptr; the value stored in the variable whose address is contained in ptr the string “ptr” the address of the variable whose address is stored in ptr the address of the variable stored in ptr
the value stored in the variable whose address is contained in ptr
Which of the following statements displays the address of the variable numb? cout<< numb; cout<< *numb; cin>>&numb; cout<<&numb;
cout<<&numb;
Which of the following statements deletes memory that has been dynamically allocated for an array? int array = delete memory; int delete[ ]; delete [] array; new array = delete;
delete [] array;
A pointer variable is designed to store any legal C++ value only floating-point values an integer a memory address
a memory address
Dynamic memory allocation occurs when a new variable is created by the compiler when a new variable is created at runtime when a pointer fails to dereference the right variable when a pointer is assigned an incorrect address
