Hi! I am Swarnima Saxena, a 3rd-year B.Tech student from the Department of Mechanical Engineering. I will be interning at Goldman Sachs in the summer of 2023. This blog covers my CDC preparation and journey. There are a lot of resources out there that tell you what to do, so let’s get started with what NOT to do.

Learning from Hindsight

• Do not start stressing about CDC at the start of your second year itself. Make sure to utilise this time to learn and explore more things. Believe me, you will thank yourself while making your CV if you know you invested your time on developing other skills/ projects instead of just doing CP.
• Competitive programming is a great hobby, not a necessity for CDC. I found coding intimidating when I started with CP. So my entire 3rd semester, I stayed away from coding because it made me feel extremely uncomfortable. It was when I properly started learning DSA that I realised it is fun. Still challenging but fun. I doubted my preparation till the very end because of the crazy fan following that CP enjoys. If you enjoy doing CP, go for it. If you don’t, still try it out. It might make clearing the coding tests slightly easier but if you don’t do it, it will definitely not kill your chances.
• Do not hesitate to reach out to people for help. Kgp has amazing people. There have been times I experienced impostor syndrome among these people and wasn’t comfortable asking for help. I seriously regret doing that and would advise you to reach out to your peers and seniors whenever you have questions, doubts or need any help. Use the great people Kgp has to offer.
• Do not underestimate the importance of mock interviews. A lot of people start giving mock contests before the coding tests start but very few are practising mock interviews. Make sure that you do both.
• Do not let self doubt control your journey. Learning how to code well has a steep learning curve. There will be days when you will feel like you are not good enough. When the CDC process starts, some tests and interviews might not go according to your plan. Do analyse your mistakes but keep going. Stick to the plan you have made for yourself.

Preparation

I started preparing for CDC at the start of my fourth semester in January. I began with practising the basics, getting proficient in C++ and getting comfortable with STL. I started practising on Leetcode but I did not have any clarity on how to proceed and soon lost track. I started exploring open source and applied to Outreachy. My initial application got selected and I started working on shortlisting the projects and trying to contribute. My final application was rejected and it was April now. CDC was just 3 months away and I was panicking.

I couldn’t make much progress from January to April in learning DSA because I lacked a clear roadmap. So this time I went for the GFG DSA self paced course. It requires around 8 weeks to complete. It’s short, crisp and affordable. I know there are a lot of free resources out there and they are equally good but this course prevented me from getting lost again. I watched video lectures and practised questions of this course and then practised the questions of the same topic from InterviewBit. After I had covered some topics, I started giving the weekly and bi-weekly contests on Leetcode to practise mixed questions with a time constraint. I also studied OOPs from youtube. I increased the frequency of Leetcode contests by the end. I also practised some questions from Brainstellar and Heard on the Street.

The time you get during summer break before CDC will be crucial. Don’t spend too much of it on perfecting your plan. Get started and stay consistent.

Shortlisting and Interview

The coding tests started around 15th July. Some were good and some went really bad. I was shortlisted for Goldman Sachs for Day1. I found out on 29th July and had my interview on 31st July.

The GS online test had a 30 min long coding section consisting of 2 medium-hard questions. Then the next two sections had MCQs on mathematics and CS fundamentals. The last section had two essay questions. The test was lengthy and time management was crucial. People were shortlisted for quant and software roles through the same test depending on which section they performed well in.

Around 60 students were shortlisted for the interviews and 14 were selected for the internship.

The interview process consisted of three rounds. In the first round, the interviewer started by asking me to give my introduction and a brief overview of my CV. I was asked two questions in this round- one was of binary tree and another of graph. I over complicated the second question but the interviewer gave me a hint and I was eventually able to solve it. At the end, he asked me to optimise it in constant space without changing the original matrix, which I wasn’t able to do. This round lasted for around 40–45 min and I was asked to wait for round 2.

The second round also had a similar format and duration. Again, I was asked two questions- I did the first one using QuickSelect and the second was a simple DP question. This round went really well and I was asked to wait for the third round. The final round was short and I was asked questions related to my CV and some general questions like why I chose software profile over my core, why I wanted to work with GS etc.

The interview process started at 11am, I got my first round around 2pm and was done with the third round by 5pm. We heard the final results around 7pm.

I had a really high fever the night before my interview, I had slept only for two hours and skipped every single meal that day. I will strictly advise you to take proper sleep, eat breakfast and stay hydrated. But if you fail to do that or feel like the circumstances aren’t great, don’t overthink it because your body’s fight or flight response will get you through it. Perceive the interview as just another problem solving session and don’t be overly nervous. In my case, my interviewers were extremely nice and helped me stay calm during the interview. Also make sure to think out loud and not stay silent for very long during the interview. Thinking out loud will not only let the interviewer judge you better but will also help you structure your thoughts more, spot your mistakes and even get a hint from the interviewer. Be prepared with your CV thoroughly because you will be questioned on it and not being able to answer those questions can take away your credibility.

Conclusion

CDC is a stressful process. Make sure you stay in touch with your friends and family. You don’t want to be alone during this period. Don’t start questioning yourself whenever you face a rejection, remember that the CDC process depends a lot on luck. Prepare well and perform your best. You will learn and grow a lot from this experience. And in the end, it will all work out.

I cannot thank CDC IIT Kharagpur enough for bringing in so many opportunities and smoothly conducting the entire process. I could not have done this without the constant support of my family and friends. That one phone call you make to your home when you hear the results make everything so completely worth it.

Feel free to reach out to me if you feel I can be of some help. All the best.