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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)
12455 AtCoder HOKUDAI-HITACHI2019-2: A. Problem C
12454 AtCoder HOKUDAI-HITACHI2019-1: B. Problem B
12453 AtCoder HOKUDAI-HITACHI2019-1: A. Problem A
12452 AtCoder HOKUDAI-HITACHI2018: C. Problem Setting C
12451 AtCoder HOKUDAI-HITACHI2018: B. Problem Setting B
12450 AtCoder HOKUDAI-HITACHI2018: A. Problem Setting A
12449 AtCoder HITACHI2020: F. Preserve Diameter
12448 AtCoder HITACHI2020: E. Odd Sum Rectangles
12447 AtCoder HITACHI2020: D. Manga Market
12446 AtCoder HITACHI2020: C. ThREE
12445 AtCoder HITACHI2020: B. Nice Shopping
12444 AtCoder HITACHI2020: A. Hitachi String
12443 AtCoder HOKUDAI-HITACHI2017-2: A. Problem 2
12442 AtCoder HOKUDAI-HITACHI2017-1: A. Problem 1
12441 AtCoder HHKB2020: F. Random Max
12440 AtCoder HHKB2020: E. Lamps
12439 AtCoder HHKB2020: D. Squares
12438 AtCoder HHKB2020: C. Neq Min
12437 AtCoder HHKB2020: B. Futon
12436 AtCoder HHKB2020: A. Keyboard
12435 AtCoder HBPC2012: D. 1+1
12434 AtCoder HBPC2012: C. 1=0.999...
12433 AtCoder HBPC2012: B. 01:01
12432 AtCoder HBPC2012: A. 1→1
12431 AtCoder GWCONTEST2015: J. ピラミッド - 2D編
12430 AtCoder GWCONTEST2015: I. ピラミッド - 立方体編
12429 AtCoder GWCONTEST2015: H. ピラミッド - デコ編
12428 AtCoder GWCONTEST2015: G. ピラミッド - 球編
12427 AtCoder GWCONTEST2015: F. ピラミッド - 誕生日編
12426 AtCoder GWCONTEST2015: E. シフト塗り分け
12425 AtCoder GWCONTEST2015: D. 最短絡問題
12424 AtCoder GWCONTEST2015: C. Snukeと対戦！
12423 AtCoder GWCONTEST2015: B. アリ巣
12422 AtCoder GWCONTEST2015: A. 得点
12421 AtCoder GIGACODE-2019: H. 論理回路の構成
12420 AtCoder GIGACODE-2019: G. ギガ国の道路事情
12419 AtCoder GIGACODE-2019: F. クローゼットの配置
12418 AtCoder GIGACODE-2019: E. 車の乗り継ぎ
12417 AtCoder GIGACODE-2019: D. 家の建設
12416 AtCoder GIGACODE-2019: C. パソコンの購入
12415 AtCoder GIGACODE-2019: B. 採用面接
12414 AtCoder GIGACODE-2019: A. 教室
12413 AtCoder GEOCON2013: D. 魔女
12412 AtCoder GEOCON2013: C. 泥棒
12411 AtCoder GEOCON2013: B. 玉座の間
12410 AtCoder GEOCON2013: A. 役人
12409 AtCoder GENOCON2021: D. Mind the Difference
12408 AtCoder GENOCON2021: C. Practice 3
12407 AtCoder GENOCON2021: B. Practice 2
12406 AtCoder GENOCON2021: A. Practice 1
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