Problem archive
Older threads, curated for practice
Past semesters, contest sets, and ODE–Integration Bee warm-ups. Use this as a practice library — and as inspiration for new problems. Tip: press / to jump into search.
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How to use the archive
- • Search by keyword, topic, difficulty, or source (semester/contest).
- • Each item opens a normal thread page: you can still read + discuss.
- • Want something added? Submit a new problem and tag it as an archive seed.
Difficulty guide
- Easy · conceptual checks, routine techniques, confidence builders
- Medium · multi-step reasoning, standard problem-solving depth
- Hard · non-trivial insight, competition-style or advanced arguments
About the archive
- • This archive contains problems that are no longer active for discussion.
- • Each entry links to its original thread for reading and reference.
- • Problems are tagged by topic, difficulty, and source for long-term clarity.