LeetCode vs Prof. Sema

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Stop memorizing concurrency diagrams. See them run. Prof. Sema is an interactive operating systems study tool for computer science students. You choose each thread's next operation, then watch shared memory, locks, queues, and blocked threads update live. MAKE THE BUG HAPPEN Try a common mistake on purpose. Create a race condition, block a thread, or build a deadlock. Prof. Sema shows exactly what changed and why. Undo the step and try a safer ordering. PRACTICE 7 CORE CONCEPTS • Race conditions and thread interleavings • Mutexes and critical sections • Semaphores using wait()/signal() and P()/V() • Producer-consumer bounded buffers • Readers-writers synchronization • Dining philosophers • AB-BA transfer deadlocks HOW IT WORKS • Pick real thread operations one step at a time • See shared state and synchronization update live • Try realistic mistakes and observe their consequences • Undo and reset freely • Open a concise explanation for each concept Use Prof. Sema for an operating systems course, exam revision, interview prep, or self-study. Every lesson works without an account. Sign in only if you want to sync progress across devices. Free. No ads. No tracking.