# Oyo Coding Interview Experience

**Online Round : **Oyo Coding visited our campus in the last week of August.

Round 1 was held on Hackerearth which comprised of around 25 MCQs and 2 coding questions. MCQs were from topics like Data Structures(mostly), Aptitude, Operating systems and DBMS.

The coding questions were

- Minimum no of ways to flip the brackets
- Given a triangle ABC and number of steps k, return the number of ways that we can arrive back at source point in k steps (1 step = traversing from one vertex to other vertex).
Example - for 2 steps, 2 possible ways (A-B-A and A-C-A). Similarly, for 3 steps, 2 possible ways(A-B-C-A and A-C-B-A).

After this 44 students were shortlisted for the PIs.

**Round 2 : **The interviewer was very friendly and patient, he primarily focused on Data Structures. He asked me three coding questions.

- First question was an implementation of Trie search and first match algorithm .He asked me to write the complete code.
- Second question was to write a complete working code to
**find the Intersection point of two linked lists.** - The third question was to print the all the nodes at kth depth in a generic tree, given the root of a generic tree.

I solved it using recursion (using depth as a variable), other method to solve is level order traversal.

Around 30 people were shortlisted for the third round.

Round** 3 : **Third round was based on Operating Systems and little of coding. The following questions were asked :

- What are scheduling algorithms and why are they used?
- What is virtual memory?
- Name and explain all the scheduling algorithms?
- What is context switch?
- Construct a binary search tree given its preorder and inorder traversal arrays. (Had to write the complete code)
- Given a source and destination in a 2D matrix, count all possible ways to reach destination from source.

Allowed steps are (x, y+1) and (x+1, y). (Complete code again)

GeeksforGeeks Link

After this round 19 people were selected. I was one of them 🙂