🚀 Coding Interview Questions with Answers (Part 3)

2️⃣1️⃣ What is Object-Oriented Programming (OOP)?

Answer:

Object-Oriented Programming (OOP) is a programming paradigm that organizes software around objects rather than functions. It helps make code modular, reusable, and easier to maintain.

The four main principles of OOP are:

• Encapsulation

• Abstraction

• Inheritance

• Polymorphism

2️⃣2️⃣ What is a Class?

Answer:

A class is a blueprint or template used to create objects. It defines the properties (attributes) and behaviors (methods) that its objects will have.

Example: A "Car" class may have properties like "color" and "speed", and methods like "start()" and "stop()".

2️⃣3️⃣ What is an Object?

Answer:

An object is an instance of a class. It contains actual values for the class's properties and can perform the actions defined by the class's methods.

Example: If "Car" is a class, then a red Toyota is an object of the "Car" class.

2️⃣4️⃣ What is Encapsulation?

Answer:

Encapsulation is the process of combining data and the methods that operate on that data into a single unit (class). It also restricts direct access to data by using access modifiers like "private", "protected", and "public".

Benefits:

• Protects data

• Improves security

• Makes code easier to maintain

2️⃣5️⃣ What is Abstraction?

Answer:

Abstraction is the concept of hiding implementation details and showing only the essential features of an object. It allows users to focus on what an object does instead of how it works.

Example: You can drive a car without knowing how the engine works internally.

2️⃣6️⃣ What is Inheritance?

Answer:

Inheritance allows one class (child/subclass) to acquire the properties and methods of another class (parent/superclass). It promotes code reuse and supports hierarchical relationships.

Example: A "Dog" class can inherit common properties and methods from an "Animal" class.

2️⃣7️⃣ What is Polymorphism?

Answer:

Polymorphism means "many forms." It allows the same method or interface to behave differently depending on the object using it.

Types:

• Compile-time Polymorphism (Method Overloading)

• Runtime Polymorphism (Method Overriding)

2️⃣8️⃣ What is Method Overloading?

Answer:

Method overloading is defining multiple methods with the same name but different parameter lists in the same class. The compiler decides which method to call based on the arguments.

Example: "add(int, int)" and "add(double, double)".

2️⃣9️⃣ What is Method Overriding?

Answer:

Method overriding occurs when a child class provides its own implementation of a method already defined in the parent class. It enables runtime polymorphism.

Example: An "Animal" class has a "sound()" method, while "Dog" overrides it to return "Bark".

3️⃣0️⃣ What is the Difference Between Method Overloading and Method Overriding?

Answer:

Method Overloading

• Occurs within the same class.

• Uses the same method name but different parameters.

• Achieves compile-time polymorphism.

• Inheritance is not required.

Method Overriding

• Occurs between parent and child classes.

• Uses the same method name and same parameters.

• Achieves runtime polymorphism.

• Requires inheritance.

🔥 Double Tap ❤️ For Part-4