TCS Technical Interview Questions

Last Updated on March 2, 2023 by Prepbytes

A technical interview is a type of job interview that focuses on the candidate’s technical skills and knowledge in a specific area, such as programming, networking, or database administration. The goal is to assess the candidate’s ability to solve technical problems and to evaluate their level of expertise. Technical interviews often include tasks such as coding challenges, system design questions, and knowledge-based questions on specific technologies or methodologies. They can be conducted in person or over the phone or through video conferencing.

About TCS

Tata Consultancy Services (TCS) is a leading global provider of information technology, consulting, and business solutions. Headquartered in Mumbai, India, TCS was founded in 1968 and is a subsidiary of the Tata Group. With a presence in 46 countries and over 450,000 employees, TCS is one of the largest IT services providers in the world. The company’s services cover a wide range of domains, including software development, application maintenance, digital transformation, IT infrastructure services, and business solutions.

TCS has a proven track record of delivering high-quality services and innovative solutions to its clients. The company has a global delivery model, which leverages its vast network of delivery centers, to offer its clients a unique combination of local and global expertise. TCS has won numerous awards and recognitions for its work, including being named a Leader in the Gartner Magic Quadrant for Global Digital Services.

In addition to its focus on delivering quality services, TCS is also committed to making a positive impact on society. The company has several sustainability initiatives, including reducing its carbon footprint and promoting diversity and inclusion in the workplace. TCS is also a strong supporter of education and has established partnerships with universities around the world to promote education and research.

In other words, TCS is a leading global IT services provider with a long history of delivering innovative solutions to its clients. The company’s commitment to quality, sustainability, and education has helped it establish a strong reputation in the industry and positioned it for continued success in the future.

TCS Technical Recruitment Process

The recruitment process of Tata Consultancy Services (TCS) typically involves the following stages:

• Online Application: Candidates can apply for positions at TCS through the company’s career website. They will need to submit their resume, cover letter, and other relevant details.
• Aptitude Test: TCS uses an online aptitude test to assess a candidate’s reasoning, numerical, and English language skills. The test is designed to measure a candidate’s potential to succeed in the role they are applying for.
• Technical Test: Based on the role, TCS may conduct a technical test to assess a candidate’s technical knowledge and skills. The test may include coding challenges, multiple-choice questions, and other types of technical assessments.
• Group Discussion: For some positions, TCS may conduct a group discussion to assess a candidate’s communication, leadership, and interpersonal skills. Candidates will be given a topic to discuss in a group setting.
• Technical Interview: The technical interview is designed to assess a candidate’s technical knowledge, experience, and problem-solving skills. The interviewer will ask questions related to the candidate’s technical background and past experience.
• HR Interview: The HR interview is designed to assess a candidate’s fit for the company and the role they are applying for. The interviewer will ask questions related to the candidate’s motivation, aspirations, and career goals.
• Offer Letter: If a candidate successfully clears all the stages of the recruitment process, TCS will offer them a position. The offer letter will include details such as the role, compensation, and start date.

Note: The recruitment process may vary based on the specific requirements of the role and the location. However, the stages outlined above are typical of TCS’s recruitment process.

Academic Criteria for TCS

Tata Consultancy Services (TCS) has different academic criteria for different roles and levels of experience. However, in general, the following academic requirements are common across most roles:

• Educational Qualification: TCS typically requires candidates to have a minimum of a bachelor’s degree in a relevant field such as computer science, engineering, mathematics, or a related discipline.
• Percentage: TCS usually requires candidates to have a minimum aggregate percentage of 60% or above throughout their academic career.
• Consistent Academic Record: TCS places significant importance on a candidate’s academic record and requires them to have a consistent academic record without any major gaps in their education.
• Additional Qualifications: For certain roles, TCS may require candidates to have additional certifications or qualifications, such as certification in a programming language or experience in a specific technology.

Note: The academic criteria may vary based on the specific requirements of the role and the location. It’s always best to check the specific requirements for the role you are applying for on TCS’s career website.

TCS Technical Interview Questions

This reference material on TCS Technical Interview Questions will assist students in learning more about the types of questions that will be asked during the Technical Interview Round. Also, keep in mind that the interviewer may occasionally ask the aspirants to write a program on paper. So, be ready to demonstrate your coding skills.

TCS Technical Interview Questions on C/C++/OOPS Concept

Here are some TCS technical interview questions on C/C++/OOPS concepts and their answers:

Q1 – Differentiate between a Structure and a Class.
Ans – Structures and classes are both used to define complex data types in programming, but there are some important differences between them:

• Inheritance: Classes support inheritance, which means that a class can inherit properties and behaviors from another class. Structures do not support inheritance.
• Access Specifiers: Classes have the ability to define access specifiers such as public, private, and protected, which control the visibility and accessibility of members. Structures do not have access specifiers and all members are public by default.
• Object-Oriented Features: Classes support object-oriented features such as encapsulation, abstraction, and polymorphism. Structures do not support these features and are limited to defining simple data types.
• Default Members: Classes have default members that are automatically generated by the compiler, such as a default constructor, copy constructor, and assignment operator. Structures do not have default members.
• Memory Allocation: Classes are dynamically allocated objects that are stored on the heap. Structures are stored on the stack and their memory is automatically deallocated when they go out of scope.

Q2 – Explain the four storage classes in C.
Ans – In C, there are four storage classes:

• Auto: The auto storage class is the default storage class for all variables defined within a function. The memory for auto variables is allocated and deallocated automatically by the compiler. The scope of auto variables is limited to the function in which they are defined.
• Register: The register storage class is used for variables that are expected to be used frequently. These variables are stored in CPU registers, which can access data much faster than memory. However, the number of registers is limited, so only a few variables can be declared as register.
• Static: The static storage class is used for variables that are defined within a function, but their values are preserved between function calls. The memory for static variables is allocated once and remains in existence for the lifetime of the program. The scope of static variables is limited to the function in which they are defined.
• External: The external storage class is used for variables that are defined outside of a function, and can be accessed by any function in the same program. The memory for external variables is allocated once and remains in existence for the lifetime of the program. The scope of external variables is the entire program.

Q3 – What are the differences between C and C++?
Ans – C++ is an extension of the C programming language and builds upon the features of C. Here are some of the key differences between C and C++:

• Object-Oriented Programming: C++ supports object-oriented programming concepts such as classes, objects, inheritance, polymorphism, and encapsulation, while C does not.
• Standard Template Library (STL): C++ includes the Standard Template Library (STL), which is a collection of templates and classes for performing common programming tasks, such as dynamic memory allocation and data structures. C does not have an equivalent.
• Exception Handling: C++ supports exception handling through the use of try-catch blocks, while C does not have a built-in mechanism for handling exceptions.
• Function Overloading: C++ allows for function overloading, which means multiple functions can have the same name, but different parameter lists. C does not support function overloading.
• Templates: C++ supports templates, which allow for generic programming and code reuse. C does not have a similar concept.
• Namespaces: C++ supports namespaces, which allow for the grouping of related variables and functions under a single name. C does not have a similar concept.
• Operator Overloading: C++ allows for operator overloading, which allows the redefinition of operators for classes. C does not support operator overloading.

Q4 – What is inheritance in OOP?
Ans – Inheritance is a mechanism that allows a new class to inherit the properties and behavior of an existing class, without having to rewrite all the code in the new class. This allows for code reuse and makes it easier to maintain and extend the code.

Q5 – Can you explain the difference between method overloading and method overriding in OOP?
Ans – In Object-Oriented Programming (OOP), method overloading and method overriding are two different concepts.

• Method Overloading: Method overloading is the ability of a class to have multiple methods with the same name but different parameter lists. The compiler can differentiate between the methods based on the number of parameters or their data types. This allows for creating multiple implementations of a method for different input scenarios.
• Method Overriding: Method overriding is the ability of a subclass to provide a new implementation for a method that is already defined in its parent class. The new implementation in the subclass must have the same method signature (name and parameter list) as the original method in the parent class. Method overriding is a key feature of polymorphism and allows for creating objects that can have different behaviors based on their actual class type, rather than their declared class type.

Q6 – What do call by value and call by reference mean?
Ans – In programming, there are two main ways to pass parameters to a function: call by value and call by reference.

Call by Value: Call by value is a method of passing parameters to a function where a copy of the value of the parameter is created and passed to the function. Changes made to the parameter within the function do not affect the original value of the parameter outside the function.

In this method, a new memory location is created for the parameter inside the function and the value of the parameter is stored in this new location. Any changes made to the parameter within the function are only reflected in this new location and do not affect the original value of the parameter.

Call by Reference: Call by reference is a method of passing parameters to a function where a reference to the memory location of the parameter is passed to the function. Changes made to the parameter within the function directly affect the original value of the parameter outside the function.

In this method, a reference to the memory location of the parameter is passed to the function. The function can then directly modify the value stored in the memory location, which is the same value that is referenced outside the function.

Q7 – Can you explain the difference between dynamic and static polymorphism in OOP?
Ans – Dynamic polymorphism refers to the ability of a method to behave differently based on the type of object being passed as an argument, while static polymorphism refers to the ability of a function to accept arguments of different types. Dynamic polymorphism is achieved through method overriding, while static polymorphism is achieved through function overloading or templates.

TCS Technical Interview Questions on Data Structures

Here are some TCS technical interview questions on Data Structures and their answers:

Q1 – What is the definition of an array? What makes it different from a linked list?
Ans – An array is a collection of elements stored in contiguous memory locations. Elements can be accessed randomly using an index. The size of an array is fixed and determined when it is declared.
A linked list is a collection of elements, called nodes, where each node has a reference to the next node in the list. Linked lists can be dynamically resized and elements are accessed in a sequential manner.

Q2 – Are linked lists linear or non-linear type?
Ans – A linked list is a linear data structure. Each node in a linked list is linked to the next node through a pointer, resulting in a linear chain of nodes. The nodes in a linked list do not have a fixed size or position in memory and can be dynamically allocated. The order of the nodes in a linked list is determined by the order in which the pointers connect them, and traversing a linked list involves following these pointers from node to node.

Q3 – What is a stack and how is it implemented?
Ans – A stack is a linear data structure that follows the Last-In-First-Out (LIFO) principle, meaning the last element that is added to the stack is the first one to be removed.

A Stack is implemented with the help of an array or a linked list. The stack has two major operations in each implementation: push and pop. Push moves an element to the top of the stack, whereas pop removes it.

In addition, to push and pop, there are other common stack operations such as peek, which returns the value of the element at the top of the stack without removing it. Another operation is isEmpty, which returns whether the stack is empty or not.

Q4 – What is a queue and how is it implemented?
Ans – A queue is a linear data structure that follows the First-In-First-Out (FIFO) principle, meaning the first element that is added to the queue is the first one to be removed.

A queue can be implemented with the help of an array or a linked list. In any version, the queue has two fundamental operations: enqueue and dequeue. Enqueue adds an element to the queue’s end, whereas dequeue removes the element from the queue’s front.

In addition, to enqueue and dequeue, there are other common queue operations such as peek, which returns the value of the element at the front of the queue without removing it. Another operation is isEmpty, which returns whether the queue is empty or not.

TCS Technical Interview Questions on DBMS

Here are some TCS technical interview questions on DBMS:

Q1 – What is DBMS?
Ans – DBMS stands for Database Management System. It is a software system that provides an interface for interacting with a database and manages the storage, retrieval, and modification of data in a database. It aims to provide a centralized way of managing data and allows multiple users to access and manipulate the same data simultaneously in a controlled and organized manner.

Q2 – What are the ACID properties of a database management system?
Ans – ACID (Atomicity, Consistency, Isolation, Durability) is a set of properties that ensure the reliability and consistency of data transactions in a database management system (DBMS).

• Atomicity: Ensures that a transaction is treated as a single, indivisible unit of work that is either completed in its entirety or not completed at all.
• Consistency: Ensures that a transaction brings the database from one consistent state to another. A transaction must follow a set of rules and constraints to maintain the consistency of the database.
• Isolation: Ensures that concurrent transactions are executed as if they are executed serially, without interference from other transactions.
• Durability: Ensures that once a transaction has been committed, its effects persist, even in the event of system failures such as power outages or crashes. This is achieved by writing the changes to a stable storage medium, such as a hard disk before the transaction is considered complete.

Q3 – What are the different Keys in DBMS?
Ans – A key is a set of attributes that can be used to uniquely identify each tuple in the given relation.

Key Types:

• Super Key – A superkey is a collection of attributes that can uniquely identify each tuple in a particular relation. A super key can have as many qualities as it wants.
• Candidate Key – A candidate key is a set of a minimal attribute(s) that can uniquely identify each tuple in the provided relation.
• Primary Key – A primary key is a candidate key chosen by the database designer while creating the database. Primary keys are distinct and NOT NULL.
• Alternate Key – Alternate keys are candidate keys that remain unimplemented or unused after the primary key has been implemented.
• Foreign Key – A foreign key is an attribute ‘X’ that is dependent on the values of another attribute ‘Y’. The referred relation is the one in which attribute ‘Y’ is present. The referenced relation is the one in which attribute ‘X’ is present.
• Composite Key – A composite key is a primary key that is made up of various attributes rather than simply one.
• Unique Key – It is unique for all records in the table. Its value cannot be modified once allocated; it is non-updatable. It could have a value of NULL.

Q4 – What is Indexing in DBMS?
Ans – Indexing is a strategy for increasing database performance by lowering the number of disc accesses required when running a query. An index is a type of data structure. It is used for quickly identifying and accessing data and information in a database table.

Q5 – What is normalization?
Ans – Normalization is the process of structuring data by dividing large tables into smaller ones with appropriate dependencies. Redundant data wastes disc space and causes maintenance issues (Update, Insert and Delete Anomaly). As a result, the database tables must be normalized.

Normalization is accomplished by adhering to certain rules known as Normal Forms. Normal Form is divided into three types: 1NF, 2NF, and 3NF.

TCS Technical Interview Questions on OS

Here are some TCS technical interview questions on OS:

Q1 – What is virtual memory?
Ans – Virtual memory is a computer system concept that enables a computer to be able to compensate for shortages of physical memory by temporarily transferring pages of data from random access memory (RAM) to disk storage. This allows a computer to run larger programs or many programs at the same time. Virtual memory essentially provides a larger pool of memory resources than the actual physical memory installed in the computer.

Q2 – What is a deadlock? Different conditions to achieve a deadlock.
Ans – A deadlock is a state where two or more processes are unable to continue executing because each process is waiting for a resource that is held by the other process.

The four conditions that must be met for a deadlock to occur are:

• Mutual exclusion: At any given time, only one process can access a resource.
• Hold and wait: A process holds a resource and requests another resource that is being held by another process.
• No preemption: The process holding the resource can only release it voluntarily.
• Circular wait: A set of processes wait for each other in a circular pattern. That is, process 1 is waiting for process 2, process 2 is waiting for process 3, and so on until process n is waiting for process 1.

Q3 – What is fragmentation?
Ans – Fragmentation refers to the process of breaking up a contiguous block of memory into smaller, non-contiguous blocks to accommodate the allocation of memory to different processes or data structures. It occurs when there is not enough contiguous memory available to allocate to a process or data structure, so the system allocates multiple blocks of memory instead.

There are two types of fragmentation: internal fragmentation and external fragmentation. Internal fragmentation occurs when a process or data structure is allocated more memory than it actually needs. External fragmentation occurs when there is enough memory available, but it is not contiguous, making it impossible for the system to allocate a single block of memory to the process or data structure.

Q4 – What are semaphores?
Ans – Semaphores are used to solve the problem of race conditions, which occurs when two or more processes attempt to access the same resource simultaneously. Semaphores provide a way for processes to communicate with each other and ensure that the resource is accessed in a mutually exclusive manner, preventing corruption of data and ensuring that the resource is used effectively.

Semaphores are usually implemented as an integer variable that is manipulated using two operations: wait (P) and signal (V). The wait operation decrements the semaphore value, and if the value is negative, the process that executed the wait operation is blocked until another process signals the semaphore. The signal operation increments the semaphore value, and if there are any blocked processes, it unblocks one of them.

Q5 – What is paging and why do we need it?
Ans – Paging is a memory management technique used in operating systems to allocate and manage the available physical memory efficiently. In paging, the physical memory is divided into small fixed-size blocks called pages, and the virtual memory is divided into equal-size blocks called page frames.

The main purpose of paging is to handle the issue of external fragmentation, which occurs when there is enough memory available, but it is not contiguous, making it impossible for the system to allocate a single block of memory to a process or data structure. With paging, the operating system can allocate memory to a process or data structure by dividing its memory requirements into smaller pages and allocating each page to a different physical memory location.

TCS Technical Interview Questions on Computer Networks

Here are some TCS technical interview questions on Computer Networks:

Q1 – What do you mean by network topology, and explain the types of them
Ans – Network topology refers to the arrangement of devices and links in a computer network, and how they communicate with each other. Network topology describes the physical and logical arrangement of nodes and links in a network.

There are various network topologies, such as:

• Star Topology: In this topology, all nodes are connected to a central device, such as a switch or hub. The central device acts as the relay between nodes, allowing communication between any two nodes in the network.
• Bus Topology: In this topology, nodes are connected to a single linear cable that acts as the communication medium. This type of topology is simple, but has a limited length and can suffer from congestion problems.
• Ring Topology: In this topology, nodes are connected to each other in a circular manner, forming a closed loop. Data is transmitted in a single direction around the ring, from one node to the next, until it reaches its destination.
• Mesh Topology: In this topology, nodes are connected to every other node in the network, providing multiple paths for data to travel. This type of topology provides high reliability and redundant links but is more complex and expensive to implement.
• Tree Topology: In this topology, nodes are organized in a hierarchical manner, with nodes at the top of the hierarchy acting as the root nodes and nodes at the bottom as leaves. This type of topology is commonly used in large networks and provides a logical way to organize and manage the network.

Q2 – Explain the TCP model
Ans – The TCP/IP model (Transmission Control Protocol/Internet Protocol) is a layered architecture of the Internet that defines how data is transmitted between two devices over a network. It consists of four layers:

• Application Layer: This layer defines the protocols and interfaces that support the user application and provide services such as file transfer, email, and network management.
• Transport Layer: The transport layer provides reliable and error-free data transmission between applications on different hosts. It also ensures that data is delivered in the correct order, and it controls flow control and congestion.
• Internet Layer: The internet layer provides the routing of data packets between networks. It provides a method for determining the optimal route for the data to travel from source to destination and uses the Internet Protocol (IP) to address and route data.
• Link Layer: The link layer provides physical communication between network devices and includes protocols for data link control and error correction. It is responsible for establishing and maintaining the physical communication link between devices.

The TCP/IP model is used as the basis for all Internet communication and provides the standard that ensures that different devices can communicate with each other over the Internet.

Q3 – Difference between IPv4 and IPv6
Ans – IPv4 and IPv6 are two versions of the Internet Protocol (IP) that are used to transmit data over the Internet. The main differences between them are:

• Address Space: IPv4 has a limited address space of 32-bit, On the other hand, IPv6 has a 128-bit address space.
• Address Representation: IPv4 uses dotted-decimal notation to represent its addresses, while IPv6 uses a hexadecimal notation separated by colons.
• Header Format: The header format of IPv4 is simpler than that of IPv6. The IPv4 header has a fixed length of 20 bytes, while the IPv6 header has a variable length.
• Support for Features: IPv6 has built-in support for advanced features such as auto-configuration, security, and mobility, which were added later in IPv4 through various extensions.
• Address Autoconfiguration: IPv6 supports automatic address configuration, which eliminates the need for manual address configuration or the use of DHCP servers.

Q4 – What happens when you enter “PrepBytes.com”
Ans – When you enter "PrepBytes.com" in a web browser, the following steps occur:

• Domain Name Resolution: The browser contacts a Domain Name System (DNS) server to resolve the domain name "PrepBytes.com" to its corresponding IP address.
• Request to the Server: The browser sends an HTTP request to the server with the resolved IP address.
• Server Response: The server receives the request and processes it, then sends back a response in the form of an HTTP message.
• Rendering the Page: The browser receives the HTTP response and renders the HTML, CSS, and JavaScript to display the webpage content of "PrepBytes.com".

FAQs on TCS Technical Interview

Here are some frequently asked questions on the TCS technical interview round:

Q1 – What kind of technical questions can I expect in a TCS technical interview?
Ans – You can expect questions on programming concepts, algorithms, data structures, databases, operating systems, software development life cycle, software testing methodologies, and system design.

Q2 – How do I prepare for coding challenges in a TCS technical interview?
Ans – You can prepare for coding challenges by practicing coding questions and problems, familiarizing yourself with commonly used algorithms and data structures, and reviewing software development and testing methodologies.

Q3 – What should I expect in a TCS technical interview for a software development role?
Ans – In a TCS technical interview for a software development role, you can expect questions on programming concepts, algorithms, data structures, software development life cycle, and software testing methodologies, as well as coding challenges.

Q4 – What should I expect in a TCS technical interview for a database administrator role?
Ans – In a TCS technical interview for a database administrator role, you can expect questions on database concepts, SQL, data modeling, database design, database optimization, and database security.

Q5 – What kind of coding questions will I face in a TCS technical interview?
Ans – You may face coding questions on algorithms, data structures, and software design. The questions may include writing code to solve a problem, debugging code, and optimizing code.

Q6 – How should I prepare for system design questions in a TCS technical interview?
Ans – To prepare for system design questions in a TCS technical interview, you can familiarize yourself with different design patterns, practice explaining how you would design and implement a solution to a complex problem, and understand trade-offs between different design choices.

Q7 – What should I focus on to prepare for a TCS technical interview?
Ans – To prepare for a TCS technical interview, you should focus on reviewing and practicing programming concepts, algorithms, data structures, databases, operating systems, software development life cycle, software testing methodologies, and system design. You should also be familiar with the latest technologies and trends in your field.