Blinkit Software Developer Interview Questions, Process, and Tips

Q1. LRU Cache - how to tackle
Ans. 
LRU Cache is a data structure that maintains a list of items in order of most recently used to least recently used.
• Implement using a doubly linked list and a hashmap for efficient operations

• When an item is accessed, move it to the front of the list

• When the cache is full, remove the least recently used item from the end of the list
Answered by AI
Add your answer
Q2. LRU Cache implementation based on a real time system. How would the main work which will be called etc etc
Add your answer

Q1. Code postorder traversal without using recursion.
Ans. 
Iterative solution using a stack to perform postorder traversal.
• Use a stack to simulate the recursive call stack.

• Push nodes in the order of right, left, root.

• Pop nodes from stack and add to result array.

• Repeat until stack is empty.
Answered by AI
Add your answer
Q2. Leetcode Problem 1626 - Best team with no conflicts.
Add your answer

Q1. Design whatsapp with one to one, group messaging and read receipts functionalities. Design the database.
Ans. 
Design a messaging app like WhatsApp with one-to-one, group messaging, and read receipts functionalities.
• Use a relational database to store user information, messages, and group memberships.

• Create tables for users, messages, groups, and group memberships.

• Include columns for message content, sender, receiver, timestamp, and read status.

• Implement a feature to mark messages as read with read receipts.

• Use indexes for effic
Answered by AI
Add your answer
Q2. Questions on dbms, cn and os.
Add your answer

3D DP, DP ON BST, Focus on highlevel dp and system design

Round duration - 120 minutes
Round difficulty - Medium

Round duration - 120 minutes
Round difficulty - Medium

- Discussion on the first round's assignment
- Was asked about adding unit tests in the assignment
- Fundamental questions on the approach used for the assignment.

Q1. What are some things that could have been done better in the system design problem given in the first round?
Ans. 
Tip 1 : Consider various edge cases.
Tip 2 : Justify the tech stack used.
Tip 3 : Write unit tests.
Answered Anonymously
Add your answer

Round duration - 90 minutes
Round difficulty - Medium

Round was with tech lead. Was briefly asked about the problem I solved in the first round. Then I was asked to solve 1 medium level DSA based question. Some discussion on culture fit was also done.

Q1. Given the frequency of traffic lights' states, can you determine if there will ever be an invalid state for the traffic signal, and what are the conditions that lead to an invalid state?
Ans. 
 Gave a brute force approach and implemented it.
 Improved upon it after getting some hint.
Answered Anonymously
Add your answer