C++ Online Quiz

Following quiz provides Multiple Choice Questions (MCQs) related to C++ Framework. You will have to read all the given answers and click over the correct answer. If you are not sure about the answer then you can check the answer using Show Answer button. You can use Next Quiz button to check new set of questions in the quiz.

Questions and Answers

Q 1 - A constructor can be virtual.

A - True

B - False

Answer : B

Explaination

The purpose of the constructor cannot be overridden in the derived class hence constructor cannot be a virtual.

Q 2 - Choose the respective delete operator usage for the expression ptr=new int[100].

A - delete ptr;

B - delete ptr[];

C - delete[] ptr;

D - []delete ptr;

Answer : C

Explaination

Q 3 - Pick up the valid declaration for overloading ++ in postfix form where T is the class name.

A - T operator++();

B - T operator++(int);

C - T& operator++();

D - T& operator++(int);

Answer : B

Explaination

The parameter int is just to signify that it is the postfix form overloaded. Shouldnt return reference as per its original behavior.

Q 4 - How many number of arguments can a destructor of a class receives?

A - 0

B - 1

C - 2

D - None of the above.

Answer : A

Explaination

The destructor receives no arguments and is only form to be provided. Hence destructor cannot be overloaded.

Q 5 - What is the output of the following program?

#include<iostream>

using namespace std;
class Base {
public:
   void f() { 
      cout<<"Base\n";
   }
};
class Derived:public Base {
public: 
   void f() {
      cout<<"Derived\n";
   };
};
main() { 
   Derived obj; 
   obj.Base::f();
}

A - Base

B - Derived

C - Compile error

D - None of the above.

Answer : A

Explaination

Base object cannot refer to Derived members.

#include<iostream>

using namespace std;
class Base {
public:
   void f() { 
      cout<<"Base\n";
  }
};
class Derived:public Base {
public: 
   void f() {
      cout<<"Derived\n";
   };
};
main() { 
   Derived obj; 
   obj.Base::f();
}

Answer : B

Explaination

Defining a templated class is defining a generic class. Hence functionality of the class is generalized for several types, if applicable.

Q 7 - What is the output of the following program?

#include<iostream>

using namespace std;
main() { 
   const int a = 5;
   
   a++; 
   cout<<a; 
}

A - 5

B - 6

C - Runtime error

D - Compile error

Answer : D

Explaination

Compile error - constant variable cannot be modified.

#include<iostream>

using namespace std;
main() { 
   const int a = 5;
   
   a++; 
   cout<<a; 
}

Q 8 - What will be the output of the following program?

#include<iostream>
#include<string.h>

using namespace std;
main() {
   cout<<strcmp("strcmp()","strcmp()");
}

A - 0

B - 1

C - -1

D - Invalid use of strcmp() function

Answer : A

Explaination

0, strcmp return 0 if both the strings are equal

#include<iostream>
#include<string.h>

using namespace std;
main() {
   cout<<strcmp("strcmp()","strcmp()");
}

Q 9 - The default executable generation on UNIX for a C++ program is ___

A - a.exe

B - a

C - a.out

D - out.a

Answer : C

Explaination

a.out is the default name of the executable generated on both the UNIX and Linux operating systems.

Q 10 - What is the output of the following program?

#include<iostream>

using namespace std;
main() { 
   class student { 
      int rno = 10;
   } v;
  
   cout<<v.rno;
}

A - 10

B - Garbage

C - Runtime error

D - Compile error

Answer : D

Explaination

Class member variables cannot be initialized.

#include<iostream>

using namespace std;
main() { 
   class student { 
      int rno = 10;
   } v;
  
   cout<<v.rno;
}
cpp_questions_answers.htm
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