Real questions asked in Cognizant GenC interviews. Each includes a preparation tip to help you frame the best answer.
Q1HR
Tell me about yourself and why you want to join Cognizant.
Tip: Cover your academic background, technical skills, and a project highlight. For the "why Cognizant" part, reference their GenC program structure, investment in fresher training, digital engineering capabilities, or specific service lines like AI, cloud, or Salesforce. Mentioning their Synapse learning platform or specific verticals (banking, healthcare, retail) shows genuine research.
Q2Technical
What is polymorphism? Explain compile-time and runtime polymorphism with examples.
Tip: Compile-time polymorphism is method overloading (same name, different parameters). Runtime polymorphism is method overriding (subclass provides a specific implementation of a parent class method). Use a Shape class with draw() method overridden in Circle and Rectangle as a clear example. Cognizant frequently uses OOP questions to gauge depth of understanding.
Q3Aptitude
A pipe can fill a tank in 6 hours and another can drain it in 8 hours. If both are open simultaneously, how long to fill the tank?
Tip: Net rate = 1/6 - 1/8 = 4/24 - 3/24 = 1/24. Time = 24 hours. Cognizant's GenC aptitude section is heavy on time and work, pipes and cisterns, and speed-distance problems. Practice identifying net rates quickly — it saves crucial time in the timed assessment.
Q4Technical
Write a program to reverse a string without using built-in reverse functions.
Tip: Use a two-pointer approach: swap characters from both ends moving inward, or iterate from the last character to first, appending to a new string. Time complexity: O(n). The GenC Next coding section expects clean, efficient solutions. Practice in Python or Java — whichever you list on your resume — and be ready to explain time and space complexity.
Q5Technical
What are the different types of SQL joins? When would you use a LEFT JOIN over an INNER JOIN?
Tip: INNER JOIN returns only matching rows in both tables. LEFT JOIN returns all rows from the left table with NULLs for non-matching right rows. Use LEFT JOIN when you need all records from the primary table regardless of a match — e.g., all customers even if they have no orders. Cognizant frequently tests joins in both the assessment and technical round.
Q6Aptitude
Find the odd one out: 4, 9, 25, 36, 49, 121
Tip: All are perfect squares except 36 (6²) — wait, 36 IS a perfect square, but 36 = 6² where 6 is even; the others are squares of odd numbers (2², 3², 5², 7², 11²). So 36 is the odd one out. Cognizant's logical reasoning section includes number classification, series completion, and pattern-finding. Look for the unifying property of the group before choosing.
Q7Technical
Explain the difference between stack and heap memory. Which is faster?
Tip: Stack memory is for static allocation — stores function calls and local variables, follows LIFO, is automatically managed, and is faster. Heap memory is for dynamic allocation, managed by the programmer (or garbage collector), and is slower due to fragmentation and pointer overhead. Mention that stack overflow occurs when recursion is too deep and heap issues lead to memory leaks.
Q8HR
Tell me about a time you failed at something. What did you learn from it?
Tip: Use the STAR method (Situation, Task, Action, Result). Pick a genuine academic or project failure — not something trivial. The key is the learning: what did you change in your approach, and what outcome did you produce after applying that lesson? Cognizant's HR rounds assess self-awareness and growth mindset heavily.
Q9Technical
What is an API? How does a REST API work?
Tip: An API (Application Programming Interface) allows software systems to communicate. A REST API uses HTTP methods: GET (read), POST (create), PUT/PATCH (update), DELETE (remove). Data is exchanged as JSON or XML. Mention statelessness as a key REST principle. With Cognizant's focus on digital engineering and cloud, API knowledge is increasingly tested even for freshers.
Q10HR
Where do you see yourself in 3 years? Are you willing to relocate to any Cognizant location?
Tip: For the 3-year plan, align your goals with Cognizant's growth tracks: becoming a subject matter expert in your tech domain, obtaining a cloud certification (AWS/Azure), or progressing to a senior analyst role. On relocation, Cognizant has offices in Chennai, Pune, Hyderabad, Bengaluru, Kolkata, and Coimbatore — express openness and see it as a career growth opportunity.