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Over 20,000 problems available: AMC 8/10/12 and AIME problems from 2010-2024; USAJMO/USAMO problems from 2002-2024; USACO problems from 2014 to 2024 (all divisions); all Codeforces, AtCoder and DMOJ problems. If you leave the search field blank, it returns all problems with the specified type.

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  • AMC 8: [year] AMC 8 Problem #, Ex: 2013 AMC 8 Problem 1
  • AMC 10: [year] AMC 10A Problem # OR [year] AMC 10B Problem #, Ex: 2015 AMC 10A Problem 16
  • AMC 12: [year] AMC 12A Problem # OR [year] AMC 12B Problem #, Ex: 2021 AMC 12B Problem 25
  • AIME: [year] AIME I Problem # OR [year] AIME II Problem #, Ex: 2013 AIME I Problem 8
  • USAJMO/USAMO: [year] USAJMO/USAMO Problem #, Ex: 2023 USAJMO Problem 1
  • Codeforces: Codeforces [contest id (e.g. 101)][problem id (e.g. A, B, C)]: [Codeforces problem name], Ex: Codeforces 1336F: Journey
  • AtCoder: AtCoder [contest id (e.g. ABC314, ARC164, ZONE2021)]: [problem id (A, B, C)]. [Problem name], Ex: AtCoder ZONE2021: E. Sneaking
  • DMOJ: DMOJ [contest name (if applicable)] [problem number (e.g. P1)] - [Problem name], Ex: DMOJ Yet Another Contest 3 P1 - Shell Swap Scam
  • USACO: [year] [contest month (e.g. January, US Open)], [division (e.g. Gold)]: [Problem name], Ex: USACO 2023 US Open Contest, Bronze: Rotate and Shift

ID Problem Name (click to add insights/hints, view summary of insights/hints and similar problems)
13305 AtCoder JSC2019-QUAL: D. Classified
13304 AtCoder JSC2019-QUAL: C. Cell Inversion
13303 AtCoder JSC2019-QUAL: B. Kleene Inversion
13302 AtCoder JSC2019-QUAL: A. Takahashi Calendar
13301 AtCoder JSC2019-FINAL: H. Distinct Integers
13300 AtCoder JSC2019-FINAL: G. Important Bridges
13299 AtCoder JSC2019-FINAL: F. Count Permutations Many Times
13298 AtCoder JSC2019-FINAL: E. Nearest String
13297 AtCoder JSC2019-FINAL: D. Minimize Maximum
13296 AtCoder JSC2019-FINAL: C. Maximize Minimum
13295 AtCoder JSC2019-FINAL: B. Reachability
13294 AtCoder JSC2019-FINAL: A. Equal Weight
13293 AtCoder JOISP2023: L. ビ太郎の旅 (Bitaro's Travel)
13292 AtCoder JOISP2023: K. 警備員 (Security Guard)
13291 AtCoder JOISP2023: J. 最後の戦い (The Last Battle)
13290 AtCoder JOISP2023: I. 旅行 (Tourism)
13289 AtCoder JOISP2023: H. クッキー (Cookies)
13288 AtCoder JOISP2023: G. ビーバーの合唱 (Chorus)
13287 AtCoder JOISP2023: F. 水ようかん 2 (Mizuyokan 2)
13286 AtCoder JOISP2023: E. 議会 (Council)
13285 AtCoder JOISP2023: D. ベルトコンベア (Belt Conveyor)
13284 AtCoder JOISP2023: C. パスポート (Passport)
13283 AtCoder JOISP2023: B. JOI 国のお祭り事情 2 (Festivals in JOI Kingdom 2)
13282 AtCoder JOISP2023: A. ふたつの通貨 (Two Currencies)
13281 AtCoder JOISC2022: L. 復興事業 (Reconstruction Project)
13280 AtCoder JOISC2022: K. 魚 2 (Fish 2)
13279 AtCoder JOISC2022: J. 一流の団子職人 (Super Dango Maker)
13278 AtCoder JOISC2022: I. 蟻と角砂糖 (Ants and Sugar)
13277 AtCoder JOISC2022: H. スプリンクラー (Sprinkler)
13276 AtCoder JOISC2022: G. 壊れた機器 2 (Broken Device 2)
13275 AtCoder JOISC2022: F. チーム戦 (Team Contest)
13274 AtCoder JOISC2022: E. 飛行機旅行 (Flights)
13273 AtCoder JOISC2022: D. コピー & ペースト 3 (Copy and Paste 3)
13272 AtCoder JOISC2022: C. スペルミス (Misspelling)
13271 AtCoder JOISC2022: B. 京都観光 (Sightseeing in Kyoto)
13270 AtCoder JOISC2022: A. 刑務所 (Jail)
13269 AtCoder JOISC2021: L. 最悪の記者 4 (Worst Reporter 4)
13268 AtCoder JOISC2021: K. 道案内 2 (Navigation 2)
13267 AtCoder JOISC2021: J. イベント巡り 2 (Event Hopping 2)
13266 AtCoder JOISC2021: I. ビーバーの会合 2 (Meetings 2)
13265 AtCoder JOISC2021: H. ボディーガード (Bodyguard)
13264 AtCoder JOISC2021: G. 古代の機械 (Ancient Machine)
13263 AtCoder JOISC2021: F. 買い物 (Shopping)
13262 AtCoder JOISC2021: E. 道路の建設案 (Road Construction)
13261 AtCoder JOISC2021: D. 逃走経路 (Escape Route)
13260 AtCoder JOISC2021: C. フードコート (Foodcourt)
13259 AtCoder JOISC2021: B. IOI 熱の感染拡大 (IOI Fever)
13258 AtCoder JOISC2021: A6. 曲芸飛行 (Aerobatics)
13257 AtCoder JOISC2021: A5. 曲芸飛行 (Aerobatics)
13256 AtCoder JOISC2021: A4. 曲芸飛行 (Aerobatics)
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