Data Structure Interview Questions

Data Structure Interview Questions

Practice Basic Data Structure Interview Questions and Answers.

Practice below the Basic Data Structure Interview Questions for the best preparation of the Data Structure Interview. These Data Structure Interview Questions are very popular and asked various times in Data Structure Interview. So, practice these questions to check your final preparation for your interview. apart from this, you can also download below the Data Structure MCQ PDF completely free.

Download Data Structure Interview Questions PDF

Below are the list of Best Data Structure Interview Questions and Answers

Object-oriented programming (OOP) is a computer programming technique that organizes software design around data, or objects, rather than functions and logic. An object can be defined as a data field that has some unique attributes and behavior.

Structured Programming can be defined as a programming Approach in which the program is made as a single structure. Lines or blocks of codes are written and executed in a sequential manner such as one instruction after the other.

It is defined as the template of similar types of objects. Class consists of state and behaviour of an object.

Object is an instance of a class that has similar characteristics.

Method is defined as the block of code that is specifically defined for a specific task.

Attributes denote the characteristics of an object.

Encapsulation refers to the winding of data into a single unit that is known as a class, while Data hiding is the process of hiding data from unauthentic and unauthorized access.

Inheritance is the ability of a class to inherit the characteristics and properties of another class. This is one of the most significant features of the object-oriented programming language. There are mainly three modes of inheritance public, protected and private and two types of classes: subclass(the one which inherits) and the base or the superclass(from which inheritance is done). And there are five ways in which inheritance can be done.

Polymorphism in object-oriented programming is the capability by which an object is able to take on numerous different forms. Polymorphism is used mainly when a reference to a child class object is made by a parent class. In Java, each and every object can be polymorphic since they can all pass the IS-A test easily. This is because an object is said to be polymorphic when it can successfully pass the IS-A test.

A Final class is defined as a class that can not be inherited further. All Methods of a final class are final, can not be redefined further, and must not be declared as final in the class definition.

An abstract class is a class that is declared with an abstract keyword. It is consists of both abstract methods and non - abstract methods. It is used to function as a base class so that it can be extended by a subclass to create a full implementation.

An interface is a shared boundary across which more than one separate component of a system exchange information. In Java, an interface is an abstract type that is used to specify a behavior that classes must implement.

A design pattern is a general repeatable solution for every task in the software design phase of software engineering. A design pattern is a structure to solve a task.

Data Structure can be defined as the structure for a group of data elements that provides an efficient way of storing and organizing data in Software engineering. For instance, Arrays, Linked List, Stack, Queue, etc

The main method is a method for software from which the execution of the software starts. Every block of a code called by it.

The class supports inheritance whereas structure does not support inheritance. Class is private by default whereas structure is public.

Class can be created for similar types of objects whereas object is only an instance of a class.

A subclass is a class that derives from the class which is known as the Superclass.

Abstract classInterface
(1) Abstract class can contain abstract and non-abstract methods that should be declared with the abstract keyword.The interface should be declared with the interface keyword. It can contain only abstract methods.
(2) Abstract class doesn't support multiple inheritances.The interfacesupports multiple inheritances.
(3) Abstract class can contain final, non-final, static, and non-static variables.The interface contains only static and final variables.
(4) Abstract class can provide the implementation of the interface.Interface can't provide the implementation of the abstract class.
(5) An abstract class can be extended by using the "extends" keyword.An interface can be implemented by using the "implements" keyword.
(6)For instance,
public abstract class Shape{
public abstract void draw();
public interface Drawable{
void draw();
(1) Constructor should not return any value.Method should return a value.
(2) Constructors are invoked implicitly.Methods are invoked explicitly.
(3) The name of the Constructor should be same as the class name.Method name should be different.
(4) Constructor is declared with construct keyword.Method should be declared with method name.
FunctionStored Procedure
(1) Function should return a value.Stored procedure may or may not return a value.
(2) Function should declared by using fun keyword.Stored Procedure may not required fun keyword.
(3) Functions can have only input parameters.Procedures can have input or output parameters.
(4) Functions can be called from Procedure.Procedures cannot be called from a Function..

When there are different methods in one class that have the same name but distinct parameters, overloading takes place. What happens at the time of overriding is that the methods have the same name as well as the same parameters. But one method here will belong to the parent class the other will belong to the child class. Also, these two are different types of concept as well, where overriding is the run-time type and the overloading is the compile-time type.

(1) Casting is the process to convert one data type to another data type by using casting operator.Conversion is process to convert a datatype into another data type automatically by compiler.
(2) Casting can be applied to compatible data types as well as incompatible data types..Conversion can only be applied to compatible datatypes.
(3) Casting is also known as Type casting.Conversion is also known as Type Conversion.
(4) Type casting is done during programming.Type conversion is done at the compile time.

Public containers would be Visible to all classes, Friendly variables would be Visible to the only same package, while Private containers would be Visible only to the container to which they belong.

Forms are visual representations that are basically used to take user’s Input or information, while Reports are gathered the information for a task that is generally shown as an output.

Normal report is represented as a document whereas a matrix report is represented in tabular format.

Both are the containers that are used to store a value. Variables are temporary whereas constants are permanent. The value of a variable may be changed during the execution but the value of constant is always fixed according to its declaration.