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)
12351	AtCoder DWANGO2015-PRELIMS: B. ニコニコ文字列
12350	AtCoder DWANGO2015-PRELIMS: A. プレミアム会員
12349	AtCoder DWANGO2015-HONSEN: D. コインの取り合い
12348	AtCoder DWANGO2015-HONSEN: C. ドライブ
12347	AtCoder DWANGO2015-HONSEN: B. コメント
12346	AtCoder DWANGO2015-HONSEN: A. ニコニコ文字列２
12345	AtCoder DWACON6TH-PRELIMS: E. Span Covering
12344	AtCoder DWACON6TH-PRELIMS: D. Arrangement
12343	AtCoder DWACON6TH-PRELIMS: C. Cookie Distribution
12342	AtCoder DWACON6TH-PRELIMS: B. Fusing Slimes
12341	AtCoder DWACON6TH-PRELIMS: A. Falling Asleep
12340	AtCoder DWACON6TH-FINAL-OPEN: D. Three Safes
12339	AtCoder DWACON6TH-FINAL-OPEN: C. Tree Shrinking
12338	AtCoder DWACON6TH-FINAL-OPEN: B. Harvest Festival
12337	AtCoder DWACON6TH-FINAL-OPEN: A. 2525敷き詰め
12336	AtCoder DWACON5TH-PRELIMS: E. Cyclic GCDs
12335	AtCoder DWACON5TH-PRELIMS: D. Square Rotation
12334	AtCoder DWACON5TH-PRELIMS: C. k-DMC
12333	AtCoder DWACON5TH-PRELIMS: B. Sum AND Subarrays
12332	AtCoder DWACON5TH-PRELIMS: A. Thumbnail
12331	AtCoder DWACON5TH-FINAL-OPEN: D. Parentheses Inversions
12330	AtCoder DWACON5TH-FINAL-OPEN: C. Interval and MST
12329	AtCoder DWACON5TH-FINAL-OPEN: B. XOR Spread
12328	AtCoder DWACON5TH-FINAL-OPEN: A. Taro vs. Jiro
12327	AtCoder DWACON2018-PRELIMS: E. ニワンゴくんの家探し
12326	AtCoder DWACON2018-PRELIMS: D. ディスクの節約
12325	AtCoder DWACON2018-PRELIMS: C. Kill/Death
12324	AtCoder DWACON2018-PRELIMS: B. 2525文字列分解
12323	AtCoder DWACON2018-PRELIMS: A. ニコニコ文字列判定
12322	AtCoder DWACON2018-FINAL-OPEN: D. ニワンゴくんとゲーム
12321	AtCoder DWACON2018-FINAL-OPEN: C. XOR ピラミッド
12320	AtCoder DWACON2018-FINAL-OPEN: B. だんだん強く
12319	AtCoder DWACON2018-FINAL-OPEN: A. アナログ時計
12318	AtCoder DP: Z. Frog 3
12317	AtCoder DP: Y. Grid 2
12316	AtCoder DP: X. Tower
12315	AtCoder DP: W. Intervals
12314	AtCoder DP: V. Subtree
12313	AtCoder DP: U. Grouping
12312	AtCoder DP: T. Permutation
12311	AtCoder DP: S. Digit Sum
12310	AtCoder DP: R. Walk
12309	AtCoder DP: Q. Flowers
12308	AtCoder DP: P. Independent Set
12307	AtCoder DP: O. Matching
12306	AtCoder DP: N. Slimes
12305	AtCoder DP: M. Candies
12304	AtCoder DP: L. Deque
12303	AtCoder DP: K. Stones
12302	AtCoder DP: J. Sushi

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

12351

AtCoder DWANGO2015-PRELIMS: B. ニコニコ文字列

12350

AtCoder DWANGO2015-PRELIMS: A. プレミアム会員

12349

AtCoder DWANGO2015-HONSEN: D. コインの取り合い

12348

AtCoder DWANGO2015-HONSEN: C. ドライブ

12347

AtCoder DWANGO2015-HONSEN: B. コメント

12346