Most Asked Data Structure Interview Questions with Answers
Are you looking for Data Structure Interview Questions? Are you preparing for Data Structure interview for job? This is the right place you have come. Here, we will guide and help you to enhance your Data Structure skills, and to be prepared for job.
Most of the product based companies ask Data Structure questions in the interview. Here, we are providing a good collection of real-world Data Structure Interview questions which are generally asked in big companies such as Google, Microsoft, Facebook, Oracle, and Amazon etc. Each question has a perfectly written answer. So, let’s start.
Que 1) What is Data Structure? / What do you understand by Data Structures?
A data structure is a logical or mechanical way that specifies how the data is organized and manipulated within a program. It also defines the relationship between them. This is important because the organization of data determines how a program performs. Data Structure is an essential part of programming so, we need to pay particular attention to the way data is structured while designing code. If we don’t store or structure data efficiently or correctly, then it would affect the overall performance, and the performance of the code will be reduced. Data Structures are the core part of computer science algorithms as they enable the programmers to handle the data efficiently.
There are many types of data structures and each has its own uses. Some popular examples of Data Structures are Arrays, Linked List, Stack, Queue, etc.
Que 2) Why is Data Structures created?
Data Structures are created to serve several numbers of important functions in a program. They make the each line of code performs its function correctly and efficiently and also help programmers to identify and fix problems with code. They also manage and create a clear and organized code base.
Que 3) What are the different types of Data Structures?
We can classify Data Structures into mainly two types:
Linear Data Structure: A Data Structure is called Linear Data Structure if its all elements are arranged in a sequential order. In Linear Data Structure, the elements are stored in a non-hierarchical form where each element has successors and predecessors except the first and the last element. Examples of linear data structures are Queue, List, Stack, Array etc.
Non-Linear Data Structure: A Data Structure is called Non-Linear Data Structure if its all elements are not arranged in a sequential order. The Non-Linear Data Structure does not form a sequence. For example, here each item or element is connected with two or more other items in a non-linear arrangement. Some examples of Non-Linear Data Structure are Tree, Graphs, BST etc.
Que 4) What are some important applications of Data Structures?
Data Structures is used mostly all the fields of IT and Computers. Some important applications of Data Structures are as follows:
- Image Processing
- Decision Making
- Compiler Design
- Database Design
- Genetics
- Blockchain
- Numerical and Statistical Analysis
Que 5) What are the different area of applications of Data Structures?
Data Structures are used extensively in the following areas of Computer Science:
- Operating System
- Database Management System
- Compiler Design
- Statistical analysis package
- Numerical Analysis
- Artificial Intelligence
- Graphics
- Simulation etc.
Que 6) Which Data Structures are used in RDBMS, Network Data Modal, and Hierarchical Data Model?
- RDBMS uses Array Data Structure
- Network Data Modal uses Graph Data Structure
- Hierarchical Data Model uses Trees Data Structure
Que 7) What is the key difference between the file structure and storage structure?
The difference between file structure and storage structure is based on memory area that is used to store and access the data. See some key differences between the file structure and storage structure:
| File Structure | Storage Structure |
| The file structure has the data stored in the auxiliary memory. | The storage structure has data stored in the memory of the computer system. |
| Here, the data is represented into secondary or auxiliary memory. For example: Any device such as a hard disks or pen drives that store data which remains intact until manually deleted is called a file structure representation. | Here, the data is stored in the main memory i.e RAM. This data is deleted once the function that uses this data is completely executed. |
Que 8) Which Data Structure is used to perform recursion?
The Stack Data Structure is used to perform recursion due to its Last In First Out (LIFO) nature. Operating System maintains the Stack Data Structure in order to save the iteration variables at each function call.
Que 9) What is the Stack Data Structure? What are the main applications of Stack Data Structure?
The Stack Data Structure is a type of Linier Data Structure that is used to represent the state of an application at a particular point of time. The stack includes a series of elements that are added to the top of the stack and then removed from the top. It follows a particular order in which operations are performed. LIFO (Last In First Out) or FILO (First In Last Out) are two possible orders. In a stack, the element that is added last will come out first.
For example: A real-life example might be a stack of clothes on top of each other or a stack of books top of each other. When we remove the cloth / book that was previously on top, we can say that the cloth /book that was added last comes out first.
Data Structure Interview Questions with Answers
