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)
1201	Codeforces 262B: Roma and Changing Signs
1200	Codeforces 262A: Roma and Lucky Numbers
1199	Codeforces 261E: Maxim and Calculator
1198	Codeforces 261D: Maxim and Increasing Subsequence
1197	Codeforces 261C: Maxim and Matrix
1196	Codeforces 261B: Maxim and Restaurant
1195	Codeforces 261A: Maxim and Discounts
1194	Codeforces 260E: Dividing Kingdom
1193	Codeforces 260D: Black and White Tree
1192	Codeforces 260C: Balls and Boxes
1191	Codeforces 260B: Ancient Prophesy
1190	Codeforces 260A: Adding Digits
1189	Codeforces 259B: Little Elephant and Magic Square
1188	Codeforces 259A: Little Elephant and Chess
1187	Codeforces 258E: Little Elephant and Tree
1186	Codeforces 258D: Little Elephant and Broken Sorting
1185	Codeforces 258C: Little Elephant and LCM
1184	Codeforces 258B: Little Elephant and Elections
1183	Codeforces 258A: Little Elephant and Bits
1182	Codeforces 257E: Greedy Elevator
1181	Codeforces 257D: Sum
1180	Codeforces 257C: View Angle
1179	Codeforces 257B: Playing Cubes
1178	Codeforces 257A: Sockets
1177	Codeforces 256E: Lucky Arrays
1176	Codeforces 256D: Liars and Serge
1175	Codeforces 255E: Furlo and Rublo and Game
1174	Codeforces 255D: Mr. Bender and Square
1173	Codeforces 255C: Almost Arithmetical Progression
1172	Codeforces 255B: Code Parsing
1171	Codeforces 255A: Greg's Workout
1170	Codeforces 254E: Dormitory
1169	Codeforces 254D: Rats
1168	Codeforces 254C: Anagram
1167	Codeforces 254B: Jury Size
1166	Codeforces 254A: Cards with Numbers
1165	Codeforces 253E: Printer
1164	Codeforces 253D: Table with Letters - 2
1163	Codeforces 253C: Text Editor
1162	Codeforces 253B: Physics Practical
1161	Codeforces 253A: Boys and Girls
1160	Codeforces 252B: Unsorting Array
1159	Codeforces 252A: Little Xor
1158	Codeforces 251E: Tree and Table
1157	Codeforces 251D: Two Sets
1156	Codeforces 251C: Number Transformation
1155	Codeforces 251B: Playing with Permutations
1154	Codeforces 251A: Points on Line
1153	Codeforces 250E: Mad Joe
1152	Codeforces 250D: Building Bridge

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

1201

Codeforces 262B: Roma and Changing Signs

1200

Codeforces 262A: Roma and Lucky Numbers

1199

Codeforces 261E: Maxim and Calculator

1198

Codeforces 261D: Maxim and Increasing Subsequence

1197

Codeforces 261C: Maxim and Matrix

1196