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)
401	Codeforces 76C: Mutation
400	Codeforces 76B: Mice
399	Codeforces 76A: Gift
398	Codeforces 75E: Ship's Shortest Path
397	Codeforces 75D: Big Maximum Sum
396	Codeforces 75C: Modified GCD
395	Codeforces 75B: Facetook Priority Wall
394	Codeforces 75A: Life Without Zeros
393	Codeforces 74E: Shift It!
392	Codeforces 74D: Hanger
391	Codeforces 74C: Chessboard Billiard
390	Codeforces 74B: Train
389	Codeforces 74A: Room Leader
388	Codeforces 73F: Plane of Tanks
387	Codeforces 73E: Morrowindows
386	Codeforces 73D: FreeDiv
385	Codeforces 73C: LionAge II
384	Codeforces 73B: Need For Brake
383	Codeforces 73A: The Elder Trolls IV: Oblivon
382	Codeforces 72I: Goofy Numbers
381	Codeforces 72H: Reverse It!
380	Codeforces 72G: Fibonacci army
379	Codeforces 72F: Oil
378	Codeforces 72E: Ali goes shopping
377	Codeforces 72D: Perse-script
376	Codeforces 72C: Extraordinarily Nice Numbers
375	Codeforces 72B: INI-file
374	Codeforces 72A: Goshtasp, Vishtasp and Eidi
373	Codeforces 71E: Nuclear Fusion
372	Codeforces 71D: Solitaire
371	Codeforces 71C: Round Table Knights
370	Codeforces 71B: Progress Bar
369	Codeforces 71A: Way Too Long Words
368	Codeforces 70E: Information Reform
367	Codeforces 70D: Professor's task
366	Codeforces 70C: Lucky Tickets
365	Codeforces 70B: Text Messaging
364	Codeforces 70A: Cookies
363	Codeforces 69E: Subsegments
362	Codeforces 69D: Dot
361	Codeforces 69C: Game
360	Codeforces 69B: Bets
359	Codeforces 69A: Young Physicist
358	Codeforces 68E: Contact
357	Codeforces 68D: Half-decay tree
356	Codeforces 68C: Synchrophasotron
355	Codeforces 68B: Energy exchange
354	Codeforces 68A: Irrational problem
353	Codeforces 67E: Save the City!
352	Codeforces 67D: Optical Experiment

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

401

Codeforces 76C: Mutation

400

Codeforces 76B: Mice

399

Codeforces 76A: Gift

398

Codeforces 75E: Ship's Shortest Path

397

Codeforces 75D: Big Maximum Sum

396