Starlight: List of Problems

Over 20,000 problems available. AMC 8/10/12 and AIME problems from 2010-2023; USAJMO/USAMO problems from 2002-2023 available. USACO problems from 2014 to 2023 (all divisions). Codeforces, AtCoder, DMOJ problems are added daily around 04:00 AM UTC, which may cause disruptions.

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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)
15001	AtCoder ZONE2021: B. Sign of Friendship
15000	AtCoder ZONE2021: A. UFO Invasion
14999	AtCoder YUHA-C88: J. 勇者最後の戦い！倒せ悪の大魔王！
14998	AtCoder YUHA-C88: I. 姫への愛情と朽ちた兜
14997	AtCoder YUHA-C88: H. 恐怖！不幸を呼ぶ盾
14996	AtCoder YUHA-C88: G. 志なかばで死んだ勇者の名は…
14995	AtCoder YUHA-C88: F. やって来たぜ！魔王城！
14994	AtCoder YUHA-C88: E. 必殺！無限覇王斬！
14993	AtCoder YUHA-C88: D. 氷柱の上の聖剣
14992	AtCoder YUHA-C88: C. 酒場の冒険者たち
14991	AtCoder YUHA-C88: B. ハヌマーンの試練
14990	AtCoder YUHA-C88: A. エンド・オブ・ビギニング
14989	AtCoder YUHA-C83: E. Camera Control - カメラ・コントロール
14988	AtCoder YUHA-C83: D. Psychic Accelerator - とある超能力の物体加速器
14987	AtCoder YUHA-C83: C. Dendrogram - 樹形図
14986	AtCoder YUHA-C83: B. Sun and Moon - 秘密結社太陽と月の団
14985	AtCoder YUHA-C83: A. Revenge of Voronoi - ボロノイの逆襲
14984	AtCoder YAHOO-PROCON2019-QUAL: F. Pass
14983	AtCoder YAHOO-PROCON2019-QUAL: E. Odd Subrectangles
14982	AtCoder YAHOO-PROCON2019-QUAL: D. Ears
14981	AtCoder YAHOO-PROCON2019-QUAL: C. When I hit my pocket...
14980	AtCoder YAHOO-PROCON2019-QUAL: B. Path
14979	AtCoder YAHOO-PROCON2019-QUAL: A. Anti-Adjacency
14978	AtCoder YAHOO-PROCON2019-FINAL: E. Espionage
14977	AtCoder YAHOO-PROCON2019-FINAL: D. Dangerous Hopscotch
14976	AtCoder YAHOO-PROCON2019-FINAL: C. Checkered Stamps
14975	AtCoder YAHOO-PROCON2019-FINAL: B. Bonsai Grafting
14974	AtCoder YAHOO-PROCON2019-FINAL: A. Affiches
14973	AtCoder YAHOO-PROCON2018-QUAL: E. グラフの問題
14972	AtCoder YAHOO-PROCON2018-QUAL: D. XOR XorY
14971	AtCoder YAHOO-PROCON2018-QUAL: C. 駆引取引
14970	AtCoder YAHOO-PROCON2018-QUAL: B. オークション
14969	AtCoder YAHOO-PROCON2018-QUAL: A. yahoo
14968	AtCoder YAHOO-PROCON2018-FINAL: E. ネットワークの構築
14967	AtCoder YAHOO-PROCON2018-FINAL: D. LCP(prefix,suffix)
14966	AtCoder YAHOO-PROCON2018-FINAL: C. 木の問題
14965	AtCoder YAHOO-PROCON2018-FINAL: B. 経路が色々
14964	AtCoder YAHOO-PROCON2018-FINAL: A. Uncommon
14963	AtCoder YAHOO-PROCON2017-QUAL: E. 遊園地
14962	AtCoder YAHOO-PROCON2017-QUAL: D. 工場
14961	AtCoder YAHOO-PROCON2017-QUAL: C. 検索
14960	AtCoder YAHOO-PROCON2017-QUAL: B. オークション
14959	AtCoder YAHOO-PROCON2017-QUAL: A. Yahoo
14958	AtCoder YAHOO-PROCON2017-FINAL: E. 瞬間移動装置
14957	AtCoder YAHOO-PROCON2017-FINAL: D. KthLIS
14956	AtCoder YAHOO-PROCON2017-FINAL: C. 倍数クエリ
14955	AtCoder YAHOO-PROCON2017-FINAL: B. チーム決め
14954	AtCoder YAHOO-PROCON2017-FINAL: A. YahooYahooYahoo
14953	AtCoder XMASCONTEST2015: H. Hybrid Testcase
14952	AtCoder XMASCONTEST2015: G. Good Sequence

Problem Name (click to add insights/hints, view summary of insights/hints and similar problems)

15001

AtCoder ZONE2021: B. Sign of Friendship

15000

AtCoder ZONE2021: A. UFO Invasion

14999

AtCoder YUHA-C88: J. 勇者最後の戦い！倒せ悪の大魔王！

14998

AtCoder YUHA-C88: I. 姫への愛情と朽ちた兜

14997

AtCoder YUHA-C88: H. 恐怖！不幸を呼ぶ盾

14996