When an ADT is implemented as a C++ class, which of the following should normally be true?

Member functions as well as member variables are private

Member functions are private, member variables are public

Member functions are public, member variables are private

Member functions as well as member variables are private

Member functions as well as member variables are public

Which of the followings is/are automatically added to every class, if we do not write our own?

A constructor without any parameter

#includeusing namespace std;class Point {public:Point() { cout

Constructor called Constructor called

24 + Mcqs in CPP Programming in Computer Science Engineering (CSE) Page 1 McqOptions

1.	When an ADT is implemented as a C++ class, which of the following should normally be true?
A.	Member functions are private, member variables are public
B.	Member functions are public, member variables are private
C.	Member functions as well as member variables are private
D.	Member functions as well as member variables are public
Answer» C. Member functions as well as member variables are private

Discussion

2.	Which of the followings is/are automatically added to every class, if we do not write our own?
A.	Copy Constructor
B.	Assignment Operator
C.	A constructor without any parameter
D.	All of the above
Answer» E.

Discussion

3.	#includeusing namespace std;class Point {public:Point() { cout << "Constructor called"; }};int main(){Point t1, *t2;return 0;}
A.	Compiler Error
B.	Constructor called Constructor called
C.	Constructor called
D.	None of the above
Answer» D. None of the above

Discussion

4.	Output of following program?#includeusing namespace std;class Point {Point() { cout << "Constructor called"; }}; int main(){Point t1;return 0;}
A.	Compiler Error
B.	Runtime Error
C.	Constructor called
D.	None of the above
Answer» B. Runtime Error

Discussion

5.	Which of the following is true about constructors?1) They cannot be virtual.2) They cannot be private.3) They are automatically called by new operator.
A.	All 1, 2, and 3
B.	Only 1 and 3
C.	Only 1 and 2
D.	Only 2 and 3
Answer» C. Only 1 and 2

Discussion

6.	Output of following C++ program?#includeusing namespace std;int main(){int x = 10;int& ref = x;ref = 20;cout << "x = " << x << endl ;x = 30;cout << "ref = " << ref << endl;return 0;}
A.	x = 20; ref = 30
B.	x = 20; ref = 20
C.	x = 10; ref = 30
D.	x = 30; ref = 30
Answer» B. x = 20; ref = 20

Discussion

7.	Which of the following is true about templates?1) Template is a feature of C++ that allows us to write one code for different data types.2) We can write one function that can be used for all data types including user defined types. Like sort(), max(), min(), ..etc.3) We can write one class or struct that can be used for all data types including user defined types. Like Linked List, Stack, Queue,..etc.4) Template is an example of compile time polymorphism.
A.	1 and 2
B.	1, 2 and 3
C.	1, 2 and 4
D.	1, 2, 3 and 4
Answer» E.

Discussion

8.	Which of the following is incorrect in C++?(1)When we write overloaded function we must code the function for each usage.(2)When we write function template we code the function only once.(3)It is difficult to debug macros(4)Templates are more efficient than macros
A.	(1) and (2)
B.	(1), (2) and (3)
C.	(3) and (4)
D.	All are correct.
Answer» E.

Discussion

9.	Which of the following are member dereferencing operators in CPP? 1. * 2. :: 3. ->* 4. ::* 5. ->
A.	Only 1, 3, 4
B.	Only 1 and 5
C.	Only 3 and 4
D.	Only 3,4,5
Answer» B. Only 1 and 5

Discussion

10.	How to create a dynamic array of pointers (to integers) of size 10 using new in C++? Hint: We can create a non-dynamic array using int *arr[10]
A.	int arr = new int [10];
B.	int *arr = new int [10];
C.	int *arr = new int [10];
D.	Not Possible
Answer» C. int *arr = new int [10];

Discussion

11.	What happens when delete is used for a NULL pointer?int *ptr = NULL;delete ptr;
A.	Compiler Error
B.	Run-time Crash
C.	No Error
D.	None
Answer» D. None

Discussion

12.	Output of following program?#include using namespace std;int fun(int=0, int = 0);int main(){cout << fun(5);return 0;}int fun(int x, int y){return (x+y);}
A.	Compiler Error
B.	5
C.	0
D.	10
Answer» C. 0

Discussion

13.	The code of statements which may cause abnormal termination of the program should be written under_________ block.
A.	Try
B.	catch
C.	Finally
D.	None of these
Answer» B. catch

Discussion

14.	Output of the program?#includeusing namespace std;int fun(int x = 0, int y = 0, int z){ return (x + y + z); }int main(){cout << fun(10);return 0;}
A.	10
B.	0
C.	20
D.	Compiler Error
Answer» E.

Discussion

15.	Predict the output?#include using namespace std;class Test{int x;Test(){x = 5;} };int main(){Test *t = new Test;cout << t->x;}
A.	Compiler Error
B.	5
C.	Garbage Value
D.	0
Answer» B. 5

Discussion

16.	Is it fine to call delete twice for a pointer?#includeusing namespace std;int main(){int *ptr = new int;delete ptr;delete ptr;return 0;}
A.	Yes
B.	No
C.	none
D.	all
Answer» C. none

Discussion

17.	In C++, const qualifier can be applied to1) Member functions of a class2) Function arguments3) To a class data member which is declared as static4) Reference variables
A.	Only 1, 2 and 3
B.	Only 1, 2 and 4
C.	All
D.	Only 1, 3 and 4
Answer» D. Only 1, 3 and 4

Discussion

18.	Which of the following is true about new when compared with malloc:1) new is an operator, malloc is a function2) new calls constructor, malloc doesn t3) new returns appropriate pointer, malloc returns void * and pointer needs to typecast to appropriate type.
A.	1 and 3
B.	2 and 3
C.	1 and 2
D.	All 1, 2 and 3
Answer» E.

Discussion

19.	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 aninstance of this class cannot be created.
A.	Both 1 and 2
B.	Only 1
C.	Only 2
D.	Neither 1 nor 2
Answer» D. Neither 1 nor 2

Discussion

20.	When the inheritance is private, the private methods in base class are __________ in the derived class (in C++).
A.	inaccessible
B.	accessible
C.	protected
D.	public
Answer» B. accessible

Discussion

21.	class Test {int x;};int main() {Test t;cout << t.x;return 0;}
A.	0
B.	Garbage Value
C.	Compiler Error
D.	None
Answer» D. None

Discussion

22.	Predict the output of following C++ program.#includeusing namespace std;class Empty {};int main() {cout << sizeof(Empty);return 0;}
A.	A non-zero value
B.	0
C.	Compiler Error
D.	Runtime Error
Answer» B. 0

Discussion

23.	Which of the following is not correct (in C++)?1. Class templates and function templates are instantiated in the same way2. Class templates differ from function templates in the way they are initiated3. Class template is initiated by defining an object using the template argument4. Class templates are generally used for storage classes
A.	(1)
B.	(2), (4)
C.	(2), (3), (4)
D.	(4)
Answer» D. (4)

Discussion

24.	When a method in a subclass has the same name and type signatures as a method in the superclass, then the method in the subclass _____ the method in the superclass.
A.	Overloads
B.	Friendships
C.	Inherits
D.	Overrides
Answer» E.

Discussion

Explore topic-wise MCQs in Computer Science Engineering (CSE).

When an ADT is implemented as a C++ class, which of the following should normally be true?

Which of the followings is/are automatically added to every class, if we do not write our own?

#includeusing namespace std;class Point {public:Point() { cout << "Constructor called"; }};int main(){Point t1, *t2;return 0;}

Output of following program?#includeusing namespace std;class Point {Point() { cout << "Constructor called"; }}; int main(){Point t1;return 0;}

Which of the following is true about constructors?1) They cannot be virtual.2) They cannot be private.3) They are automatically called by new operator.

Output of following C++ program?#includeusing namespace std;int main(){int x = 10;int& ref = x;ref = 20;cout << "x = " << x << endl ;x = 30;cout << "ref = " << ref << endl;return 0;}

Which of the following is incorrect in C++?(1)When we write overloaded function we must code the function for each usage.(2)When we write function template we code the function only once.(3)It is difficult to debug macros(4)Templates are more efficient than macros

Which of the following are member dereferencing operators in CPP? 1. * 2. :: 3. ->* 4. ::* 5. ->

How to create a dynamic array of pointers (to integers) of size 10 using new in C++? Hint: We can create a non-dynamic array using int *arr[10]

What happens when delete is used for a NULL pointer?int *ptr = NULL;delete ptr;

Output of following program?#include using namespace std;int fun(int=0, int = 0);int main(){cout << fun(5);return 0;}int fun(int x, int y){return (x+y);}

The code of statements which may cause abnormal termination of the program should be written under_________ block.

Output of the program?#includeusing namespace std;int fun(int x = 0, int y = 0, int z){ return (x + y + z); }int main(){cout << fun(10);return 0;}

Predict the output?#include using namespace std;class Test{int x;Test(){x = 5;} };int main(){Test *t = new Test;cout << t->x;}

Is it fine to call delete twice for a pointer?#includeusing namespace std;int main(){int *ptr = new int;delete ptr;delete ptr;return 0;}

In C++, const qualifier can be applied to1) Member functions of a class2) Function arguments3) To a class data member which is declared as static4) Reference variables

Which of the following is true about new when compared with malloc:1) new is an operator, malloc is a function2) new calls constructor, malloc doesn t3) new returns appropriate pointer, malloc returns void * and pointer needs to typecast to appropriate type.

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 aninstance of this class cannot be created.

When the inheritance is private, the private methods in base class are __________ in the derived class (in C++).

class Test {int x;};int main() {Test t;cout << t.x;return 0;}

Predict the output of following C++ program.#includeusing namespace std;class Empty {};int main() {cout << sizeof(Empty);return 0;}

When a method in a subclass has the same name and type signatures as a method in the superclass, then the method in the subclass _____ the method in the superclass.