Codeforces
Competitive programming contests and an enormous free problem archive, harder than interview material and excellent for building raw speed under pressure. Optional for interviews, and it makes them feel easy.
Platform
Interview Prep
Codeforces
Ongoing
Advanced
Free
What it is
The main competitive programming platform, running frequent rated contests with an archive of tens of thousands of problems, all free.
How it relates to interviews
Indirectly but usefully. Competitive problems are harder and more mathematical than interview problems, so this is not efficient preparation. What it builds is speed, accuracy under a clock, and comfort with the feeling of being stuck, and those transfer completely. Candidates who compete tend to find interview problems slow rather than difficult.
The honest caveat
If your interview is in six weeks, do not start here. Work a curated interview list instead. This is worth doing when you have time, when you enjoy it, or when you want a ceiling well above what any interview will ask.
Best for: students, and engineers who want the difficulty ceiling raised well past interview level.
Ready to start?
Opens on Codeforces in a new tab.
Stuck on something specific?
Writing only gets you so far. If you want an answer to your situation rather than the general case, book a session and we will work through it together. Every session is free; a few slots open each week.
Follow along
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