OYO ASDE Interview Experience

OYO Rooms visited our campus for its recruitment drive for the Associate Software Development Engineer position.

The selection process had an initial screening, followed by an online coding assessment and a technical interview. Although the coding assessment went quite well, the technical interview was a different experience altogether.

Round 1: Online Assessment (OA)

The process started with an initial screening, after which approximately 100-130 students were shortlisted for the coding assessment.

The assessment was conducted on campus and included four programming questions. The overall difficulty was around easy to medium.

Most of the questions tested basic problem-solving skills and commonly used DSA patterns, including:

• Sliding Window

• Two Pointers

• Array-based problems

• Basic DP Problem

I was able to solve all four questions within the given assessment.

After the evaluation, only seven students were shortlisted for the technical interview. This made the next stage quite competitive.

Round 2: Technical Interview

The technical interview was conducted online. The interviewer focused mainly on DSA and problem-solving.

I was given two coding problems during this round.

Question 1: Maximum Money Robbed in a Binary Tree

Topics: Binary Trees, Tree DP, Recursion, Dynamic Programming

The first problem involved a binary tree where every node represented the amount of money available in a house.

The objective was to calculate the maximum amount of money that could be collected, with one important condition: two directly connected houses (parent and child) could not be robbed together.
Similar Problem:

How I approached it:

I started by thinking recursively about the two choices available at every node:

• Rob the current node and skip its immediate children.

• Skip the current node and consider robbing its children.

The idea was to calculate the maximum possible amount for both choices and use these results to determine the best outcome.

I approached it using recursion and two states for every node:

1. Maximum amount when the current node is robbed.

2. Maximum amount when the current node is skipped.

This allowed the solution to avoid making locally optimal decisions without considering their impact on the rest of the tree.

Question 2: Maximum Number of Events That Can Be Attended

Topics: Greedy, Sorting, Intervals, Min Heap

The second problem was based on scheduling events.

We were given multiple events, each having a starting day and an ending day. The condition was that only one event could be attended on any particular day.

The task was to find the maximum number of events that could be attended.

How I approached it:

I considered a greedy strategy combined with sorting and a Min Heap.

The general approach was:

1. Sort all events according to their starting days.

2. Maintain a Min Heap containing the ending days of available events.

3. For each day, add events that have started.

4. Remove events that have already expired.

5. Attend the event that ends earliest.

6. Repeat the process to maximise the total number of events attended.

The important observation here was that choosing the event that finishes earliest leaves more opportunities to attend other events later.

This problem required a good understanding of interval scheduling and priority queue operations.

After discussing the interview experiences with my classmates, I found that the questions weren't limited to just these two problems.

Other candidates also encountered questions involving:

• Linked Lists

• Binary Trees

• Tree-based problem-solving

• Different DSA concepts

Overall, the technical interviews seemed to place a strong emphasis on data structures and algorithmic thinking.