WB JECA MCA Object Oriented Programming OOPs Previous Year Questions (PYQs)
A Place for Latest Exam wise Questions, Videos, Previous Year Papers,
Study Stuff for MCA Examinations
Study Stuff for MCA Examinations
Showing 10 questions
Find the output from the following C++ code snippet:
class A
{
public: void show()
{
cout<<"Class A
";
}
};
class B: public A
{
public: void show()
{
A::show();
cout<<"Class B";
}
};
int main()
{
B obj;
obj.show();
}
1
2
3
4
Solution
Calls A::show then prints Class B.
What will be the output of this program? class Test { public: static int x; Test() { x++; } void display() { cout<
#include
using namespace std;
1
2
3
4
Solution
x=5 → t1→6, t2→7.
How many parameters does a default constructor require ?
(A) 1
(B) 2
(C) 0
(D) 3
1
2
3
4
Solution
- A default constructor in C++ is a constructor that takes no arguments.
- It is invoked automatically when an object is created without passing parameters.
Correct Answer: (C) 0
What is the output of the following C++ code? class Base { public: virtual void show() { cout<<"Base"; } }; class Derived: public Base { public: void show() override{ cout<<"Derived"; } }; int main() { Base* ptr; Derived d; ptr=&d; ptr->show(); return 0; }
#include
using namespace std;
1
2
3
4
Solution
Virtual function → Derived called.
The keyword friend does not appear in
(A) the class allowing access to another class.
(B) the class desiring access to another class.
(C) the private section of a class.
(D) the public section of a class.
1
2
3
4
Solution
- The
friendkeyword is used inside a class definition to allow another class or function to access its private/protected members. - It appears in the class granting access (not the one desiring access).
- It can be declared in either public or private section of that class.
Correct Answer: (B) the class desiring access to another class
Which among the following can’t be used for polymorphism?
1
2
3
4
Solution
Solution: Static member functions cannot be virtual; hence they don’t participate in runtime polymorphism.
Overloading (functions/operators/constructors) supports polymorphism.
Answer: (A) Static member functions
Answer: (A) Static member functions
If a file has read and write permission for the owner, then the octal representation of the permissions will be:
1
2
3
4
Solution
Solution: Read=4, Write=2 ⇒ total = 6.
Answer: (C) 6
Answer: (C) 6
Identify the incorrect constructor type:
1
2
3
4
Solution
Solution: In C++, there is no concept of Friend Constructor. Others exist.
Answer: (A) Friend Constructor
Answer: (A) Friend Constructor
Making class members inaccessible to nonmember functions is an example of:
1
2
3
4
Solution
Solution: Restricting access to internal details of a class is data hiding (encapsulation).
Answer: (B) data hiding
Answer: (B) data hiding
Which is the correct statement about operator overloading ?
1
2
3
4
Solution
Solution: Overloading changes operator meaning for user types, but its precedence and associativity never change.
Answer: (D)
Answer: (D)
WB JECA MCA
Online Test Series, Information About Examination,
Syllabus, Notification
and More.
View More
WB JECA MCA
Online Test Series, Information About Examination,
Syllabus, Notification
and More.
View More
Ask Your Question or Put Your Review.
