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)
13501	AtCoder MATH-AND-ALGORITHM: 029. Climb Stairs
13500	AtCoder MATH-AND-ALGORITHM: 027. Sorting
13499	AtCoder MATH-AND-ALGORITHM: 001. Print 5+N
13498	AtCoder M-SOLUTIONS2020: F. Air Safety
13497	AtCoder M-SOLUTIONS2020: E. M's Solution
13496	AtCoder M-SOLUTIONS2020: D. Road to Millionaire
13495	AtCoder M-SOLUTIONS2020: C. Marks
13494	AtCoder M-SOLUTIONS2020: B. Magic 2
13493	AtCoder M-SOLUTIONS2020: A. Kyu in AtCoder
13492	AtCoder M-SOLUTIONS2019: F. Random Tournament
13491	AtCoder M-SOLUTIONS2019: E. Product of Arithmetic Progression
13490	AtCoder M-SOLUTIONS2019: D. Maximum Sum of Minimum
13489	AtCoder M-SOLUTIONS2019: C. Best-of-(2n-1)
13488	AtCoder M-SOLUTIONS2019: B. Sumo
13487	AtCoder M-SOLUTIONS2019: A. Sum of Interior Angles
13486	AtCoder LOADCHECKING: A. 好きな順列
13485	AtCoder KUPC2021: M. Formula
13484	AtCoder KUPC2021: L. Tag Game
13483	AtCoder KUPC2021: K. Three Coloring
13482	AtCoder KUPC2021: J. Delete Balls
13481	AtCoder KUPC2021: I. Good LACK
13480	AtCoder KUPC2021: H. Symmetric
13479	AtCoder KUPC2021: G. Two Step Sort
13478	AtCoder KUPC2021: F. One Yen Coin
13477	AtCoder KUPC2021: E. PERMST
13476	AtCoder KUPC2021: D. Stones
13475	AtCoder KUPC2021: C. Gacha
13474	AtCoder KUPC2021: B. Painting with Many Orders
13473	AtCoder KUPC2021: A. Standing Sign
13472	AtCoder KUPC2020: M. Many Parentheses
13471	AtCoder KUPC2020: L. Inside Story of Median Query
13470	AtCoder KUPC2020: K. Deleting Edges
13469	AtCoder KUPC2020: J. Median Query
13468	AtCoder KUPC2020: I. Coloring Paths
13467	AtCoder KUPC2020: H. Beans on the Grid
13466	AtCoder KUPC2020: G. Counting Angels
13465	AtCoder KUPC2020: F. GRIDMST
13464	AtCoder KUPC2020: E. Sequence Partitioning
13463	AtCoder KUPC2020: D. Stick Combination
13462	AtCoder KUPC2020: C. Grid and Substrings
13461	AtCoder KUPC2020: B. Numbers on Papers
13460	AtCoder KUPC2020: A. Classroom Distance
13459	AtCoder KUPC2019: L. タケノコ
13458	AtCoder KUPC2019: K. One or All
13457	AtCoder KUPC2019: J. Link-cut tworee
13456	AtCoder KUPC2019: I. encode/decode 2019
13455	AtCoder KUPC2019: H. 123パズル
13454	AtCoder KUPC2019: G. ABCのG問題
13453	AtCoder KUPC2019: F. カズマ王国の陥落
13452	AtCoder KUPC2019: E. 根付き森二人用ゲーム

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

13501

AtCoder MATH-AND-ALGORITHM: 029. Climb Stairs

13500

AtCoder MATH-AND-ALGORITHM: 027. Sorting

13499

AtCoder MATH-AND-ALGORITHM: 001. Print 5+N

13498

AtCoder M-SOLUTIONS2020: F. Air Safety

13497

AtCoder M-SOLUTIONS2020: E. M's Solution

13496