Since the placement season is starting soon, here is a prioritized compilation of the minimum knowledge required to clear most software interviews.
The word minimum is used deliberately - this guide only covers essentials, not everything.
I have written it in priority wise order so the things which are written on top are more important than bottom. So start learning from top to bottom.
Have at least one good project on your resume. The tech stack doesn't matter, but it should be worth discussing for at least 15 minutes.
Prepare all technologies mentioned in your resume. If you're not confident about something, remove it.
DSA is asked in almost every company. If you can solve at least LeetCode medium problems by yourself without hints, you can clear most companies' DSA rounds.
If you haven't done DSA yet, you can speed-run the InterviewBit problem set (~270 questions): https://www.interviewbit.com/courses/programming/
Learn OOP concepts thoroughly: class, object, interface, inheritance, compile-time & runtime polymorphism.
Best playlist for C++ OOPs: YouTube - C++ OOPs Playlist
Watch at 2x speed and skip question videos. Can be completed in 2 days.
Even if your interviews don't have dedicated HLD rounds, knowing the basics will help in explaining your projects and CS questions.
Sufficient resource: System Design for Beginners
No prerequisites required to understand this.
No need to watch big DBMS playlists. Above is sufficient.
After OOPs, learn the SOLID principles and then the following patterns:
Practice the following LLD questions:
If CN questions will be asked, then 99% chances are they are limited to only the above 3 topics.
Since you now know basic OS, DBMS, CN, and HLD - practice the following HLD questions:
This knowledge is sufficient to clear HLD rounds.
If you don't have good preparation then don't feel sad. It involves luck also, you can get good placement with less knowledge.
If you prepared very well and not able to secure good placement in future then also don't feel sad because it involves luck which is not in your hand.
All the best! 🚀