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)
301	Codeforces 58B: Coins
300	Codeforces 58A: Chat room
299	Codeforces 57E: Chess
298	Codeforces 57D: Journey
297	Codeforces 57C: Array
296	Codeforces 57B: Martian Architecture
295	Codeforces 57A: Square Earth?
294	Codeforces 56E: Domino Principle
293	Codeforces 56D: Changing a String
292	Codeforces 56C: Corporation Mail
291	Codeforces 56B: Spoilt Permutation
290	Codeforces 56A: Bar
289	Codeforces 55E: Very simple problem
288	Codeforces 55D: Beautiful numbers
287	Codeforces 55C: Pie or die
286	Codeforces 55B: Smallest number
285	Codeforces 55A: Flea travel
284	Codeforces 54E: Vacuum Сleaner
283	Codeforces 54D: Writing a Song
282	Codeforces 54C: First Digit Law
281	Codeforces 54B: Cutting Jigsaw Puzzle
280	Codeforces 54A: Presents
279	Codeforces 53E: Dead Ends
278	Codeforces 53D: Physical Education
277	Codeforces 53C: Little Frog
276	Codeforces 53B: Blog Photo
275	Codeforces 53A: Autocomplete
274	Codeforces 52C: Circular RMQ
273	Codeforces 52B: Right Triangles
272	Codeforces 52A: 123-sequence
271	Codeforces 51F: Caterpillar
270	Codeforces 51E: Pentagon
269	Codeforces 51D: Geometrical problem
268	Codeforces 51C: Three Base Stations
267	Codeforces 51B: bHTML Tables Analisys
266	Codeforces 51A: Cheaterius's Problem
265	Codeforces 50E: Square Equation Roots
264	Codeforces 50D: Bombing
263	Codeforces 50C: Happy Farm 5
262	Codeforces 50B: Choosing Symbol Pairs
261	Codeforces 50A: Domino piling
260	Codeforces 49E: Common ancestor
259	Codeforces 49D: Game
258	Codeforces 49C: Disposition
257	Codeforces 49B: Sum
256	Codeforces 49A: Sleuth
255	Codeforces 48H: Black and White
254	Codeforces 48G: Galaxy Union
253	Codeforces 48F: Snow sellers
252	Codeforces 48E: Ivan the Fool VS Gorynych the Dragon

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

301

Codeforces 58B: Coins

300

Codeforces 58A: Chat room

299

Codeforces 57E: Chess

298

Codeforces 57D: Journey

297

Codeforces 57C: Array

296