Binary SemaphoreBinary Semaphore/learn
mentorshiptopicsroadmapsnotebooks
sign in
CC++JavaPythonJavaScriptTypeScriptGoDSAOperating SystemsNetworksDatabasesSystem DesignTheory and CompilersMaths for CSFrontendBackend and APIsSecurityCloud and DevOpsTestingAIGit and the ShellDebuggingInterviews and Viva
DSA
  • patterns-that-repeat
  • where-people-freeze
  • complexity-in-interviews
  • the-questions-that-get-asked
  • whiteboard-without-panic

© 2026 Binary Semaphore

discord

DSA

Complexity, out loud

Stating it correctly and confidently, including what Big O deliberately ignores.

We have not written this one up yet, and it would be easy to pretend otherwise.

Want this written up?

Sign in and tell us. We write the ones people actually ask for, and asking takes one click.

Sign in to ask

Or sit with someone on it instead of waiting for us to write it.

What we have

Nothing yet, and no canonical source worth pointing at.

Book an hour on this