My interview experience at ION Trading Group for DEV profile (Rejected)

Hi guys,

So I think, I have grown up! now I'm in my final year and posting after 1+ year. Here is my interview experience at ION Trading.

ION Group visited our campus in August last week. It was a pool campus drive. The eligibility Criteria were 7.5+ CGPA and CSE, and ECE branches were allowed.

Online Assessment Round

The first round was the online assessment round. It was a two-hour long test. There were 2 coding questions and around 15-16 MCQ problems. MCQ was related to CS fundamentals, programming language, time complexity, SQL query, English proficiency, etc. The first coding question was related to strings. I was able to solve using brute force and around 11/15 test cases were passed. Probably it was supposed to be solved using the KMP algorithm. The second question was a standard DP knapsack problem: Two arrays are given, presentStockPrice, futureStockPrice you need to maximize the profit given a budget. I was able to pass all the test cases.

Interview Round – 1

Out of 100 students, 25 were shortlisted for the interview rounds. The interview started with my introduction, interviewer also introduced himself. He asked me about my projects. There were some questions asked related to my tech stack :

1. Why have you opted for the MERN stack?
2. What are the advantages of MERN over other alternatives?
3. What differences did you see when you used react instead of vanila JS for front end?
4. Why have you opted for MongoDB for your project?
5. What type of schema your project has : Structured or Unstructured?
6. What is horizontal and vertical scaling?
7. Why haven’t you used SQLite etc for your project when your schema is structured?

After project discussion he started with OOPS concept. He asked literally everything A to Z about OOPS in C++. Starting from basic definition, four pillars of OOPS, their classification, real world examples etc. Later he asked me to write code for Operator overloading for binary addition operator to use as String concatenation operator for a class. I wrote the code successfully. Then he start giving some various cases where multiple classes are inheriting from each other, he asked about sequence of constructor calling if we create an object of last descendant class. After that he asked same thing for destructor calling. Later asked about can we pass an object as argument in a function. He asked me to write code for runtime polymorphism. Asked about virtual function, friend function, static variable, function. Overall there was solid grilling on OOPS concept.

After OOPS, he gave me a DSA problem : Given a singly linked list head return the k-th node from the reverse. I wrote the code using brute force in which I first calculated the length and then traversed len-k nodes. But he asked me to write code using one pass. I tried with two pointers method but couldn’t complete it.

He also asked some time complexity related question like insertion and deletion in stack, search in Binary Search tree. Asked about Quick sort complexity and code but I didn’t know the code for this algorithm. After this he asked me a puzzle Two wire puzzle GFG . I tried for around 10 minutes but couldn’t come up with exact solutions. He also helped me but I wasn’t able to come up with exact logic.

Finally the interview ended with followup question from my end about financial learning from working at ION. Overall the interview lasted for around 75 minutes.

Verdict : I was not shortlisted for next round.

For other candidates there were 2 more round online and 3 rounds held at ION Noida campus. All rounds were non technical kind of. They asked about case studies, project discussion, behavioural questions etc.

Tip: Know everything about OOPS, GFG top puzzles and your projects.

Thanks for visiting my blog!