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)
13901	AtCoder PAST202010-OPEN: J. ワープ
13900	AtCoder PAST202010-OPEN: I. ピザ
13899	AtCoder PAST202010-OPEN: H. マス目のカット
13898	AtCoder PAST202010-OPEN: G. 村整備
13897	AtCoder PAST202010-OPEN: F. 構文解析
13896	AtCoder PAST202010-OPEN: E. アナグラム
13895	AtCoder PAST202010-OPEN: D. 分身
13894	AtCoder PAST202010-OPEN: C. 隣接カウント
13893	AtCoder PAST202010-OPEN: B. 電卓
13892	AtCoder PAST202010-OPEN: A. 中央値
13891	AtCoder PAST202005-OPEN: O. Quoits
13890	AtCoder PAST202005-OPEN: N. Swap and Sort
13889	AtCoder PAST202005-OPEN: M. Real Traveling Salesman
13888	AtCoder PAST202005-OPEN: L. Supamarket
13887	AtCoder PAST202005-OPEN: K. Moving Containers
13886	AtCoder PAST202005-OPEN: J. Sushi-go-round
13885	AtCoder PAST202005-OPEN: I. Matrix Operations
13884	AtCoder PAST202005-OPEN: H. Hurdling
13883	AtCoder PAST202005-OPEN: G. Gold General Goes on the Grid
13882	AtCoder PAST202005-OPEN: F. Palindromic Matrix
13881	AtCoder PAST202005-OPEN: E. Sprinklers
13880	AtCoder PAST202005-OPEN: D. Digital Display
13879	AtCoder PAST202005-OPEN: C. Geometric Progression
13878	AtCoder PAST202005-OPEN: B. Dynamic Scoring
13877	AtCoder PAST202005-OPEN: A. Case Sensitive
13876	AtCoder PAST202004-OPEN: O. Variable Spanning Trees
13875	AtCoder PAST202004-OPEN: N. Building Construction
13874	AtCoder PAST202004-OPEN: M. Cafeteria
13873	AtCoder PAST202004-OPEN: L. Lexicographically Minimum
13872	AtCoder PAST202004-OPEN: K. Parentheses
13871	AtCoder PAST202004-OPEN: J. Parse
13870	AtCoder PAST202004-OPEN: I. Elimination
13869	AtCoder PAST202004-OPEN: H. 1-9 Grid
13868	AtCoder PAST202004-OPEN: G. String Query
13867	AtCoder PAST202004-OPEN: F. Tasking
13866	AtCoder PAST202004-OPEN: E. Permutation
13865	AtCoder PAST202004-OPEN: D. String Match
13864	AtCoder PAST202004-OPEN: C. Landslide
13863	AtCoder PAST202004-OPEN: B. Plurality Voting
13862	AtCoder PAST202004-OPEN: A. Elevator
13861	AtCoder PAST201912-OPEN: O. Endurance
13860	AtCoder PAST201912-OPEN: N. Land Clearing
13859	AtCoder PAST201912-OPEN: M. Auto Choice
13858	AtCoder PAST201912-OPEN: L. Gradation
13857	AtCoder PAST201912-OPEN: K. Conglomerate
13856	AtCoder PAST201912-OPEN: J. Leveling
13855	AtCoder PAST201912-OPEN: I. Procurement
13854	AtCoder PAST201912-OPEN: H. Bulk Selling
13853	AtCoder PAST201912-OPEN: G. Division
13852	AtCoder PAST201912-OPEN: F. DoubleCamelCase Sort

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

13901

AtCoder PAST202010-OPEN: J. ワープ

13900

AtCoder PAST202010-OPEN: I. ピザ

13899

AtCoder PAST202010-OPEN: H. マス目のカット

13898

AtCoder PAST202010-OPEN: G. 村整備

13897

AtCoder PAST202010-OPEN: F. 構文解析

13896