# OYO Rooms Interview Experience | Set 21 (On Campus)

**Coding Round: **It had 20 MCQ’s and 2 coding questions**.**

**First question was:**

- Given a source and destination in a NxN maze find the shortest path between them, some of the cells are occupied and one cannot find path through them.
https://practice.geeksforgeeks.org/problems/shortest-source-to-destination-path/0

**Second question was**:

- Given
**d**,**a**,**b**and an array of integers. You can add/subtract**a**and**b**to**d**any number of times. You have to find the count of array elements which can be formed by applying these operations to**d.**

30 students were selected for the F2F interviews out of 150.

**Round 1: **The interviewer was very friendly. The round began with usual introduction and then he asked me DS/Algo questions**.**

- Implement a Data structure in which following operations can be done efficiently (a) find max element (b) insert (c) delete any element
- Write code for all operations of Heap data structure.
- Find the sum of last n nodes of the given linked list
- Given a Binary tree which can contain values only 0 and 1. You need to find and of nodes in left and right subtree. If a node has only one or zero child then don’t change its value.

**This round lasted around an hour. 21 students were selected for the second round.**

**Round 2: **After the introduction part he asked me OS related questions.

- There was detailed discussion on what is Deadlock, conditions for deadlock, methods for removing deadlock
- Then he asked me some questions on my projects which I had mentioned in my resume. He told me to write all use cases of a project.
- Then he asked some web related questions – what is tomcat server, what is difference between App server and Web server.
- He asked me one design problem – Build a system where a student can prepare resume according to format specified by the University.
- At last he asked me one coding question – Print all cycles in a directed graph.

Finally, they selected 13 students from my college and thankfully I was one of them.