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)
951	Codeforces 202A: LLPS
950	Codeforces 201E: Thoroughly Bureaucratic Organization
949	Codeforces 201D: Brand New Problem
948	Codeforces 201C: Fragile Bridges
947	Codeforces 201B: Guess That Car!
946	Codeforces 201A: Clear Symmetry
945	Codeforces 200E: Tractor College
944	Codeforces 200D: Programming Language
943	Codeforces 200C: Football Championship
942	Codeforces 200B: Drinks
941	Codeforces 200A: Cinema
940	Codeforces 199B: Special Olympics
939	Codeforces 199A: Hexadecimal's theorem
938	Codeforces 198E: Gripping Story
937	Codeforces 198D: Cube Snake
936	Codeforces 198C: Delivering Carcinogen
935	Codeforces 198B: Jumping on Walls
934	Codeforces 198A: About Bacteria
933	Codeforces 197B: Limit
932	Codeforces 197A: Plate Game
931	Codeforces 196E: Opening Portals
930	Codeforces 196D: The Next Good String
929	Codeforces 196C: Paint Tree
928	Codeforces 196B: Infinite Maze
927	Codeforces 196A: Lexicographically Maximum Subsequence
926	Codeforces 195E: Building Forest
925	Codeforces 195D: Analyzing Polyline
924	Codeforces 195C: Try and Catch
923	Codeforces 195B: After Training
922	Codeforces 195A: Let's Watch Football
921	Codeforces 194B: Square
920	Codeforces 194A: Exams
919	Codeforces 193E: Fibonacci Number
918	Codeforces 193D: Two Segments
917	Codeforces 193C: Hamming Distance
916	Codeforces 193B: Xor
915	Codeforces 193A: Cutting Figure
914	Codeforces 192B: Walking in the Rain
913	Codeforces 192A: Funky Numbers
912	Codeforces 191E: Thwarting Demonstrations
911	Codeforces 191D: Metro Scheme
910	Codeforces 191C: Fools and Roads
909	Codeforces 191B: Demonstration
908	Codeforces 191A: Dynasty Puzzles
907	Codeforces 190E: Counter Attack
906	Codeforces 190D: Non-Secret Cypher
905	Codeforces 190C: STL
904	Codeforces 190B: Surrounded
903	Codeforces 190A: Vasya and the Bus
902	Codeforces 189B: Counting Rhombi

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

951

Codeforces 202A: LLPS

950

Codeforces 201E: Thoroughly Bureaucratic Organization

949

Codeforces 201D: Brand New Problem

948

Codeforces 201C: Fragile Bridges

947

Codeforces 201B: Guess That Car!

946