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)
1151	Codeforces 250C: Movie Critics
1150	Codeforces 250B: Restoring IPv6
1149	Codeforces 250A: Paper Work
1148	Codeforces 249E: Endless Matrix
1147	Codeforces 249D: Donkey and Stars
1146	Codeforces 248E: Piglet's Birthday
1145	Codeforces 248D: Sweets for Everyone!
1144	Codeforces 248C: Robo-Footballer
1143	Codeforces 248B: Chilly Willy
1142	Codeforces 248A: Cupboards
1141	Codeforces 246E: Blood Cousins Return
1140	Codeforces 246D: Colorful Graph
1139	Codeforces 246C: Beauty Pageant
1138	Codeforces 246B: Increase and Decrease
1137	Codeforces 246A: Buggy Sorting
1136	Codeforces 245H: Queries for Number of Palindromes
1135	Codeforces 245G: Suggested Friends
1134	Codeforces 245F: Log Stream Analysis
1133	Codeforces 245E: Mishap in Club
1132	Codeforces 245D: Restoring Table
1131	Codeforces 245C: Game with Coins
1130	Codeforces 245B: Internet Address
1129	Codeforces 245A: System Administrator
1128	Codeforces 244B: Undoubtedly Lucky Numbers
1127	Codeforces 244A: Dividing Orange
1126	Codeforces 243E: Matrix
1125	Codeforces 243D: Cubes
1124	Codeforces 243C: Colorado Potato Beetle
1123	Codeforces 243B: Hydra
1122	Codeforces 243A: The Brand New Function
1121	Codeforces 242E: XOR on Segment
1120	Codeforces 242D: Dispute
1119	Codeforces 242C: King's Path
1118	Codeforces 242B: Big Segment
1117	Codeforces 242A: Heads or Tails
1116	Codeforces 241G: Challenging Balloons
1115	Codeforces 241F: Race
1114	Codeforces 241E: Flights
1113	Codeforces 241D: Numbers
1112	Codeforces 241C: Mirror Box
1111	Codeforces 241B: Friends
1110	Codeforces 241A: Old Peykan
1109	Codeforces 240F: TorCoder
1108	Codeforces 240E: Road Repairs
1107	Codeforces 239B: Easy Tape Programming
1106	Codeforces 239A: Two Bags of Potatoes
1105	Codeforces 238E: Meeting Her
1104	Codeforces 238D: Tape Programming
1103	Codeforces 238C: World Eater Brothers
1102	Codeforces 238B: Boring Partition

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

1151

Codeforces 250C: Movie Critics

1150

Codeforces 250B: Restoring IPv6

1149

Codeforces 250A: Paper Work

1148

Codeforces 249E: Endless Matrix

1147

Codeforces 249D: Donkey and Stars

1146