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)
7901	Codeforces 1701C: Schedule Management
7900	Codeforces 1701B: Permutation
7899	Codeforces 1701A: Grass Field
7898	Codeforces 1700F: Puzzle
7897	Codeforces 1700E: Serega the Pirate
7896	Codeforces 1700D: River Locks
7895	Codeforces 1700C: Helping the Nature
7894	Codeforces 1700B: Palindromic Numbers
7893	Codeforces 1700A: Optimal Path
7892	Codeforces 1699E: Three Days Grace
7891	Codeforces 1699D: Almost Triple Deletions
7890	Codeforces 1699C: The Third Problem
7889	Codeforces 1699B: Almost Ternary Matrix
7888	Codeforces 1699A: The Third Three Number Problem
7887	Codeforces 1698G: Long Binary String
7886	Codeforces 1698F: Equal Reversal
7885	Codeforces 1698E: PermutationForces II
7884	Codeforces 1698D: Fixed Point Guessing
7883	Codeforces 1698C: 3SUM Closure
7882	Codeforces 1698B: Rising Sand
7881	Codeforces 1698A: XOR Mixup
7880	Codeforces 1697F: Too Many Constraints
7879	Codeforces 1697E: Coloring
7878	Codeforces 1697D: Guess The String
7877	Codeforces 1697C: awoo's Favorite Problem
7876	Codeforces 1697B: Promo
7875	Codeforces 1697A: Parkway Walk
7874	Codeforces 1696H: Maximum Product?
7873	Codeforces 1696G: Fishingprince Plays With Array Again
7872	Codeforces 1696F: Tree Recovery
7871	Codeforces 1696E: Placing Jinas
7870	Codeforces 1696D: Permutation Graph
7869	Codeforces 1696C: Fishingprince Plays With Array
7868	Codeforces 1696B: NIT Destroys the Universe
7867	Codeforces 1696A: NIT orz!
7866	Codeforces 1695E: Ambiguous Dominoes
7865	Codeforces 1695D2: Tree Queries (Hard Version)
7864	Codeforces 1695D1: Tree Queries (Easy Version)
7863	Codeforces 1695C: Zero Path
7862	Codeforces 1695B: Circle Game
7861	Codeforces 1695A: Subrectangle Guess
7860	Codeforces 1694B: Paranoid String
7859	Codeforces 1694A: Creep
7858	Codeforces 1693F: I Might Be Wrong
7857	Codeforces 1693E: Outermost Maximums
7856	Codeforces 1693D: Decinc Dividing
7855	Codeforces 1693C: Keshi in Search of AmShZ
7854	Codeforces 1693B: Fake Plastic Trees
7853	Codeforces 1693A: Directional Increase
7852	Codeforces 1692H: Gambling

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

7901

Codeforces 1701C: Schedule Management

7900

Codeforces 1701B: Permutation

7899

Codeforces 1701A: Grass Field

7898

Codeforces 1700F: Puzzle

7897

Codeforces 1700E: Serega the Pirate

7896