Round 1 (Codility Online Test)
Questions:
- There are some recipes [pasta, maggi, pizza,.....] and there is an ingredient string given "pamstaagagi". You need to find out what recipes can be made using this ingredient string.
- Output - [pasta, maggi]
- There is a car assembly factory, in which there are two parallel lanes making identical parts. Ex - A and B. There is a cost X for moving A to B and cost Y for moving B to A. We need to find the minimum cost to complete all the operations. No cost in moving down in the same lane.
- Example - A - [1, 6, 2] B - [3, 2, 5], X = 2, Y = 1
- Output = 8 = 1 + 2 + 2 + 1 + 2
Candidate's Approach
No approach provided.
Interviewer's Feedback
No feedback provided.
Round 2 (Coding Interview)
Questions:
-
There is a sorted array {1,2,2,2,2,3,3,4,4,4}, need to find out how many times a given element is present in this array. Time complexity should be O(log(n)) in the worst-case scenario also - LeetCode Discussion
-
There is a given array {1,-1,3,-1,2,9,-8, 6}. Need to return a list of all the combinations which have a sum equal to zero.
- Output = [[-1,-1,2],[2,-8,6]] - LeetCode Problem
Candidate's Approach
No approach provided.
Interviewer's Feedback
No feedback provided.
Round 3 (System Design)
Questions:
- High level and low level design for generating tiny URL.
- How is redirection happening from tiny URL to actual URL?
- What are the hashing techniques you have used? (like Base64, Base62, SHA1, etc.)
- How many types of load balancers have you used?
Candidate's Approach
No approach provided.
Interviewer's Feedback
No feedback provided.
Round 4 (System Design) (Rejected)
Questions:
- You have given buses and routes, how to map these buses to certain routes to optimize bus usage.
- Similar LeetCode Question - Bus Routes
- Design a system for the given use case - If any bus is deviating from the route or exceeding the given speed limit, an alert should be sent to the system.
Some useful findings regarding the above question:
Candidate's Approach
No approach provided.
Interviewer's Feedback
No feedback provided.
Overall, the experience was OK; learned a few things also. It was my first interview after so many years, so I could not clear the 4th round. Any leads will be appreciated regarding where to prepare for these kinds of system design interview questions.