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)
14901	AtCoder XMASCON18: D. Devilish Dice
14900	AtCoder XMASCON18: C. CombinatioN
14899	AtCoder XMASCON18: B. Bit Smaller
14898	AtCoder XMASCON18: A. Art Time
14897	AtCoder XMASCON17: I. SAT Puzzle
14896	AtCoder XMASCON17: H. Ango
14895	AtCoder XMASCON17: G. Maze
14894	AtCoder XMASCON17: F. Tree Disassembly
14893	AtCoder XMASCON17: E. String Problem
14892	AtCoder XMASCON17: D. Inversion Number
14891	AtCoder XMASCON17: C. Revenge of Kurousa
14890	AtCoder XMASCON17: B. Hello, Xmas Contest 2017
14889	AtCoder XMASCON17: A. Compressor
14888	AtCoder XMASCON16MIDNIGHT: J. Just a Single Testcase
14887	AtCoder XMASCON16MIDNIGHT: I. ISOLT
14886	AtCoder XMASCON16MIDNIGHT: H. High-powered Illuminations
14885	AtCoder XMASCON16MIDNIGHT: G. Guide Passengers
14884	AtCoder XMASCON16MIDNIGHT: F. Fifty-Fifty?
14883	AtCoder XMASCON16MIDNIGHT: E. Examination, Estimation
14882	AtCoder XMASCON16MIDNIGHT: D. Distributed Sorting
14881	AtCoder XMASCON16MIDNIGHT: C. Cutting Swiss Roll
14880	AtCoder XMASCON16MIDNIGHT: B. Binary Tree
14879	AtCoder XMASCON16MIDNIGHT: A. Array Sum
14878	AtCoder WUPC2ND: I. その味は甘くて
14877	AtCoder WUPC2ND: H. ダイヤグラム
14876	AtCoder WUPC2ND: G. だるま落とし
14875	AtCoder WUPC2ND: F. 僕は宇宙人
14874	AtCoder WUPC2ND: E. 独立記念日
14873	AtCoder WUPC2ND: D. 5キューブ
14872	AtCoder WUPC2ND: C. 至高のケーキ
14871	AtCoder WUPC2ND: B. 雨上がり
14870	AtCoder WUPC2ND: A. 団子とうさぎ
14869	AtCoder WUPC2019: J. Color Ball
14868	AtCoder WUPC2019: I. Ramen
14867	AtCoder WUPC2019: H. Doki Doki Programming Clubs!
14866	AtCoder WUPC2019: G. Teishoku
14865	AtCoder WUPC2019: F. RPG
14864	AtCoder WUPC2019: E. Artist
14863	AtCoder WUPC2019: D. Choose Your Characters
14862	AtCoder WUPC2019: C. Permutation City
14861	AtCoder WUPC2019: B. 10 puzzle
14860	AtCoder WUPC2019: A. WAsedAC
14859	AtCoder WUPC2012: F. 最後の問題
14858	AtCoder WUPC2012: E. 会場への道
14857	AtCoder WUPC2012: D. 三角パズル
14856	AtCoder WUPC2012: C. 自宅からの脱出
14855	AtCoder WUPC2012: B. パスワード
14854	AtCoder WUPC2012: A. 招待状
14853	AtCoder WTF19-OPEN: E. e
14852	AtCoder WTF19-OPEN: D. Distinct Boxes

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

14901

AtCoder XMASCON18: D. Devilish Dice

14900

AtCoder XMASCON18: C. CombinatioN

14899

AtCoder XMASCON18: B. Bit Smaller

14898

AtCoder XMASCON18: A. Art Time

14897

AtCoder XMASCON17: I. SAT Puzzle

14896