Oracle visited our campus for virtual hiring for two roles: Server Technology and Application Engineer.

Around 500 students appeared for the online test.

Round 1: Online Test (107 minutes)

Initially, an online test was conducted on Oracle's own proctored platform (camera and microphone enabled). The test comprised multiple sections, each with subsections that had a fixed time limit for completion.

The sections included:

• Aptitude
• Data Structures and Algorithms (DSA) concepts, primarily AVL trees, threaded binary search trees, and flowchart completion
• Computer Science theory from Operating Systems (OS), Database Management Systems (DBMS), Object-Oriented Programming (OOPs), and Software Engineering
• English-based aptitude and reasoning questions

Approximately 40 students were shortlisted for each profile for the subsequent stages of the hiring process. I was selected for the Application Engineer profile.

The round started with an introduction of both myself and the interviewer.

I was asked just one coding question in this round. I had to write full working code on a shared CoderPad.

The question was: given an arithmetic expression like 4+(5*2)/3-1, I had to determine whether the given arithmetic expression is valid or not.

https://codereview.stackexchange.com/questions/181606/determine-if-simple-arithmetic-expression-is-valid/181657

I proposed a stack-based approach, and the interviewer was satisfied. He then asked me to solve it without using a stack. I was able to code that as well.

For each of my approaches, he provided 18-20 test cases with different errors, such as unbalanced parentheses or consecutive operands (e.g., 4++2). Both of my approaches passed all these test cases.

Finally, he gave me two test cases that contained spaces, like (4 2). My stack solution gave the wrong answer for this. I was about to rectify the solution, but due to the paucity of time, he said it was alright.

I was selected for the next round.