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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)
11905 AtCoder CADDI2018B: B. AtCoder Alloy
11904 AtCoder CADDI2018B: A. 12/22
11903 AtCoder CADDI2018: F. Square
11902 AtCoder CADDI2018: E. Negative Doubling
11901 AtCoder CADDI2018B: D. Harlequin
11900 AtCoder CADDI2018B: C. Product and GCD
11899 AtCoder BITFLYER2018-QUAL: E. 祝日
11898 AtCoder BITFLYER2018-QUAL: D. ハンコ
11897 AtCoder BITFLYER2018-QUAL: C. 徒歩圏内
11896 AtCoder BITFLYER2018-QUAL: B. 洋菓子店
11895 AtCoder BITFLYER2018-QUAL: A. 本選参加者数
11894 AtCoder BITFLYER2018-FINAL: H. 三角形と格子点
11893 AtCoder BITFLYER2018-FINAL: G. Following Permutations
11892 AtCoder BITFLYER2018-FINAL: F. 配信パズル
11891 AtCoder BITFLYER2018-FINAL: E. 数式とクエリ
11890 AtCoder BITFLYER2018-FINAL: D. 数列 XOR
11889 AtCoder BITFLYER2018-FINAL: C. 部分文字列と括弧
11888 AtCoder BITFLYER2018-FINAL: B. 交通費
11887 AtCoder BITFLYER2018-FINAL: A. 値札
11886 AtCoder BIRTHDAY0410: X. この問題はほんとうにひどい問題であるため，できれば先に他の問題のほうをお楽しみいただければと思っておりまして，ですので他の問題を通し終えて暇になり，かつその暇を
11885 AtCoder BIRTHDAY0410: F. おいらの素数生成式
11884 AtCoder BIRTHDAY0410: E. 排他的☆論理和っ！！
11883 AtCoder BIRTHDAY0410: D. 先生と遺書
11882 AtCoder BIRTHDAY0410: C. ロ　シ　ア
11881 AtCoder BIRTHDAY0410: B. ライスゲーム
11880 AtCoder BIRTHDAY0410: A. A + B
11879 AtCoder BCU30: F. 数列と計算
11878 AtCoder BCU30: E. スライドパズル
11877 AtCoder BCU30: D. 数直線
11876 AtCoder BCU30: C. クロスワード
11875 AtCoder BCU30: B. 数字パズル
11874 AtCoder BCU30: A. すごろく
11873 AtCoder BCU30-2019-QUAL: A. Bullet of Flame
11872 AtCoder BCU30-2019: B. Interval Addition
11871 AtCoder BCU30-2019: A. Wolf Keyboard
11870 AtCoder BCU30-2018-QUAL: A. Age
11869 AtCoder BCU30-2018: B. Spring Water
11868 AtCoder BCU30-2018: A. Ball
11867 AtCoder AUTUMN_FEST: K. Batch Style Mastermind
11866 AtCoder AUTUMN_FEST: J. Ninja of Train
11865 AtCoder AUTUMN_FEST: I. Pyramid
11864 AtCoder AUTUMN_FEST: H. U・N・C・O
11863 AtCoder AUTUMN_FEST: G. Bit Map
11862 AtCoder AUTUMN_FEST: F. Vinculum
11861 AtCoder AUTUMN_FEST: E. Be Together
11860 AtCoder AUTUMN_FEST: D. Don't Think Seriously!
11859 AtCoder AUTUMN_FEST: C. Cards
11858 AtCoder AUTUMN_FEST: B. 3Match
11857 AtCoder AUTUMN_FEST: A. Irregular Contest
11856 AtCoder ATCODER11LIVE: A. Turn Right
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