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)
151	Codeforces 32E: Hide-and-Seek
150	Codeforces 32D: Constellation
149	Codeforces 32C: Flea
148	Codeforces 32B: Borze
147	Codeforces 32A: Reconnaissance
146	Codeforces 31E: TV Game
145	Codeforces 31D: Chocolate
144	Codeforces 31C: Schedule
143	Codeforces 31B: Sysadmin Bob
142	Codeforces 31A: Worms Evolution
141	Codeforces 30E: Tricky and Clever Password
140	Codeforces 30D: King's Problem?
139	Codeforces 30C: Shooting Gallery
138	Codeforces 30B: Codeforces World Finals
137	Codeforces 30A: Accounting
136	Codeforces 29E: Quarrel
135	Codeforces 29D: Ant on the Tree
134	Codeforces 29C: Mail Stamps
133	Codeforces 29B: Traffic Lights
132	Codeforces 29A: Spit Problem
131	Codeforces 28E: DravDe saves the world
130	Codeforces 28D: Don't fear, DravDe is kind
129	Codeforces 28C: Bath Queue
128	Codeforces 28B: pSort
127	Codeforces 28A: Bender Problem
126	Codeforces 27E: Number With The Given Amount Of Divisors
125	Codeforces 27D: Ring Road 2
124	Codeforces 27C: Unordered Subsequence
123	Codeforces 27B: Tournament
122	Codeforces 27A: Next Test
121	Codeforces 26E: Multithreading
120	Codeforces 26D: Tickets
119	Codeforces 26C: Parquet
118	Codeforces 26B: Regular Bracket Sequence
117	Codeforces 26A: Almost Prime
116	Codeforces 25E: Test
115	Codeforces 25D: Roads not only in Berland
114	Codeforces 25C: Roads in Berland
113	Codeforces 25B: Phone numbers
112	Codeforces 25A: IQ test
111	Codeforces 24E: Berland collider
110	Codeforces 24D: Broken robot
109	Codeforces 24C: Sequence of points
108	Codeforces 24B: F1 Champions
107	Codeforces 24A: Ring road
106	Codeforces 23E: Tree
105	Codeforces 23D: Tetragon
104	Codeforces 23C: Oranges and Apples
103	Codeforces 23B: Party
102	Codeforces 23A: You're Given a String...

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

151

Codeforces 32E: Hide-and-Seek

150

Codeforces 32D: Constellation

149

Codeforces 32C: Flea

148

Codeforces 32B: Borze

147

Codeforces 32A: Reconnaissance

146