Paytm || Senior Software Engineer || September 2024 || Round 1

Round 1

Questions:

Question

1. Check if there is a loop in a linked list. Return a boolean value. Example:

   1 -> 2 -> 3 -> 4
           |
           4 <- 5

   Response: true
   Similar to this Question - Leetcode

2. PRINT ALL THE SUBSETS OF THE FOLLOWING ARRAY
   Arr = [A,B,C] ->
   RESPONSE: A, B, C, AB, BC, CA, ABC

3. Leetcode Question

Design Question:
Consider a situation where you are working in Paytm Recharge section and you want to send notification to the user if your MB is very low, e.g., if you have 1.5 GB and your data is around 50MB left, you have to send notification to the user that your MB is low.
Scale to consider - 100M Notifications per day
Database Design to consider: Store 100M writes per day
Also, you have to do analytics on top of the database.