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.

Q 1 - Choose the operator which cannot be overloaded.

Answer : C

Explaination

Scope resolution (::) is not permitted to be overloaded.

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

Answer : C

Explaination

Q 3 - Runtime polymorphism is done using.

A - Function overloading

B - Virtual classes

C - Virtual functions

D - Friend function

Answer : C

Explaination

Virtual functions gives the ability to override the functionality of base class into the derived class. Hence achieving dynamic/runtime polymorphism.

Q 4 - Class function which is called automatically as soon as the object is created is called as __

Answer : A

Explaination

If not provided the same, default constructor from the compiler is called automatically otherwise the programmer’s provided constructor gets called.

Q 5 - The programs machine instructions are store in __ memory segment.

Answer : D

Explaination

Code segments holds the program instructions and fetched by instruction pointer for execution.

Q 6 - A C++ program statements can be commented using

A - Single line comment

B - Multi line comment

C - Either (a) or (b)

D - Both (a) and (b).

Answer : D

Explaination

Both styles of commenting is available in C++.

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

#include<iostream>

using namespace std;
main() {
   short unsigned int i = 0; 
   
   cout<<i--;
}

Answer : A

Explaination

0, with post decrement operator value of the variable will be considered as the expression’s value and later gets decremented

#include<iostream>

using namespace std;
main() {
   short unsigned int i = 0; 
   
   cout<<i--;
}

Q 8 - What is the output of the following program?

#include<iostream>

using namespace std;
void swap(int m, int n) {
   int x = m;

	m = n;
	n = x;
}
main() {
   int x = 5, y = 3;
   
	swap(x,y);
	cout<<x<<" "<<y;
}

Answer : B

Explaination

5 3, call by value mechanism can’t alter actual arguments.

#include<iostream>

using namespace std;
void swap(int m, int n) {
   int x = m;

	m = n;
	n = x;
}
main() {
   int x = 5, y = 3;
   
	swap(x,y);
	cout<<x<<" "<<y;
}

Q 9 - Choose the invalid identifier from the below

Answer : B

Explaination

bool is the reserved keyword and cannot be used an identifier name.

Q 10 - Does both the loops in the following programs prints the correct string length?

#include<iostream>

using namespace std;
main() {
   int i;
   
   char s[] = "hello";

   for(i=0; s[i]; ++i);
      cout<<i<<endl;

   i=0; 
   
   while(s[i++]);
      cout<<i;
}

A - Yes, both the loops prints the correct length

B - Only for loop prints the correct length

C - Only while loop prints the correct length

D - Compile error in the program.

Answer : B

Explaination

In while loop 'i' gets incremented after checking for '\0', hence giving 1 more than the length.

#include<iostream>

using namespace std;
main() {
   int i;
   
   char s[] = "hello";

   for(i=0; s[i]; ++i);
      cout<<i<<endl;

   i=0;
   
   while(s[i++]);
      cout<<i;
}

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