# OYO Rooms Interview Experience for Software Developer (On-Campus)

• Difficulty Level : Medium
• Last Updated : 19 Nov, 2020

OYO Rooms visited our campus for Recruiting SDE-1. Eligible Branches were CSE, IT, ECE, EEE.

CGPA Cutoff: 7

Round 1(Online Coding Round): The Online Round consists of 2 coding questions and 15 MCQ questions based on OS, OOPS, DBMS, and DSA.

Coding Questions were:

1. Print a given matrix in spiral form
2. In this question, you will be given x co-ordinate and y co-ordinate as input, there is a building at that co-ordinate whose height will also be given as input. Now again you will be given x co-ordinate and y co-ordinate as input this pair of co-ordinates will be the top-right coordinates of a rectangle and the bottom left coordinate of the rectangle is at (1,1) always. You have to find the height of the largest building in the rectangle.

Example: At (1,1) building height is 2, At (1,2) building height is 3, At (2,2) building height is 5. Again (2,2) is given as input this is the top right co-ordinate of the rectangle whose bottom left co-ordinate is (1,1). For this particular example output will be 5 (Building at (2,2)). Also, assume the height of the building as 0 for the rest of the co-ordinates.

After the test 35 students were shortlisted for interviews. I solved the first question completely and the second one part and was shortlisted for the interviews.

Round 2 (Technical Interview 1): The Interview began with a brief discussion about the projects that I have on my resume, very basic questions were asked on that. After which I was asked 2 DSA questions in that round.

1. The first question was given an array of pairs you have to tell whether there exist inverse of a given pair or not.

Example:

```arr[] = {{11, 20}, {30, 40}, {5, 10}, {40, 30}, {10, 5}}.
Here {{30,40} - {40,30}} & {{5,10} - {10,5}} are inverse of each other.```

I first gave a solution in time complexity O(n^2). Then I was further asked to optimize the complexity, after thinking a bit a gave a solution in time complexity O(n) and space complexity O(n) but I was using two maps in my approach. Then I was asked to reduce the space complexity by using only 1 map. I also gave a solution for that. The number of traversals required in my approach was 2 (1 for traversing the array and creating the map and the other for checking the inverse pair) now I was asked to think of an approach using only 1 traversal. After giving the best approach I was asked to Code it.

2. The second question was to do vertical order traversal of a binary tree.

I gave a map-based solution using BFS. Then I was asked why you didn’t use DFS. Well, you can use both only differences will be in the order of occurrence of nodes of right subtree. After that, I was asked to Code my approach.

That was all in the first round of Technical interviews, it lasted for about an hour and the interviewer was very friendly always ready to give you hints you just need to tell them exactly where you are getting stuck.

Round 3 (Technical Interview 2): Began with an informal discussion about my general routine during lock-down. Then some basic oops and os questions were asked. After that, I was given the first DSA question of that round, given two nodes of a binary tree you have to tell them whether they are cousins or not.

I gave him an approach where I was using two functions, one to check if they have the same parent or not i.e. sibling, and the second function to obtain the level of both the node. So, if they don’t have the same parents, and they are on the same level that means they are cousins. After which I was asked to Code my approach.

Then I was asked to design a game, He explained the entire game to me and I have to design that game using concepts of oops. Here just try to say whatever is coming to your mind try to interact as much as possible with the interviewer. I did the same and he was pretty satisfied. That was all for this round.

After that, some students also have their 3rd round of technical interview.

In the end, the result was declared and a total of 8 students were selected including me. I hope my experience will help.

P.S. If you have projects and internships on your resume then that’s good but if you don’t you need not worry cause what ultimately matters is your DATA STRUCTURES and ALGORITHMS.

My Personal Notes arrow_drop_up