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)
18551	DMOJ Mock CCC '19 Contest 2 S1 - Tudor's Double Doors
18550	DMOJ Mock CCC '19 Contest 2 J5 - Tudor Drinks Even More Tea
18549	DMOJ Mock CCC '19 Contest 2 J4 - Tudor Buys Some Cheesecake
18548	DMOJ Mock CCC '19 Contest 2 J3 - Tudor Buys Some Tea
18547	DMOJ Mock CCC '19 Contest 2 J2 - Tudor Drinks Some More Tea
18546	DMOJ Mock CCC '19 Contest 2 J1 - Tudor Drinks Some Tea
18545	DMOJ Mock CCC '19 Contest 1 S5 - Pusheen Eats Even More Tuna Sashimi and Tuna Nigiri
18544	DMOJ Mock CCC '19 Contest 1 S4 - Pusheen Plays Neko Atsume
18543	DMOJ Mock CCC '19 Contest 1 S3 - Pusheen Eats Tuna Sashimi and Tuna Nigiri
18542	DMOJ Mock CCC '19 Contest 1 S2 - Pusheen's Puzzle Present
18541	DMOJ Mock CCC '19 Contest 1 S1 - Pusheen's Report Card
18540	DMOJ Mock CCC '19 Contest 1 J5 - Pusheen Designs a Sushi Boat
18539	DMOJ Mock CCC '19 Contest 1 J4 - Pusheen Plays Neko Atsume
18538	DMOJ Mock CCC '19 Contest 1 J3 - Pusheen Eats Tuna Sashimi and Tuna Nigiri
18537	DMOJ Mock CCC '19 Contest 1 J2 - Pusheen OCR
18536	DMOJ Mock CCC '19 Contest 1 J1 - Pusheen's Report Card
18535	DMOJ Mock CCC '18 Contest 5 S5 - California Boggle
18534	DMOJ Mock CCC '18 Contest 5 S4 - Sparse Binary String Counting
18533	DMOJ Mock CCC '18 Contest 5 J5/S3 - Directed Graph Connectivity
18532	DMOJ Mock CCC '18 Contest 5 J4/S2 - Reverse Sort
18531	DMOJ Mock CCC '18 Contest 5 J3/S1 - Median Triples
18530	DMOJ Mock CCC '18 Contest 5 J2 - Smallest Mode
18529	DMOJ Mock CCC '18 Contest 5 J1 - Looking for the CCC
18528	DMOJ Mock CCC '18 Contest 3 S5 - A Rage Tree Problem
18527	DMOJ Mock CCC '18 Contest 3 S4 - A Graph Problem
18526	DMOJ Mock CCC '18 Contest 3 J5/S3 - A Cookie-Cutter Problem
18525	DMOJ Mock CCC '18 Contest 3 J4/S2 - A Median Problem
18524	DMOJ Mock CCC '18 Contest 3 J3/S1 - A String Problem
18523	DMOJ Mock CCC '18 Contest 3 J2 - A Palindrome Problem
18522	DMOJ Mock CCC '18 Contest 3 J1 - A Sum Problem
18521	DMOJ Mock CCC '18 Contest 2 S5 - A Link/Cut Tree Problem
18520	DMOJ Mock CCC '18 Contest 2 S4 - A Tree Problem
18519	DMOJ Mock CCC '18 Contest 2 J5/S3 - A Coloring Problem
18518	DMOJ Mock CCC '18 Contest 2 J4/S2 - A Geometry Problem
18517	DMOJ Mock CCC '18 Contest 2 J3/S1 - An Array Problem
18516	DMOJ Mock CCC '18 Contest 2 J2 - A Software Engineering Task
18515	DMOJ Mock CCC '18 Contest 2 J1 - An Arithmetic Problem
18514	DMOJ Mock CCC '18 Contest 1 S5 - A Palindrome Problem
18513	DMOJ Mock CCC '18 Contest 1 S4 - A Graph Problem
18512	DMOJ Mock CCC '18 Contest 1 J5/S3 - A Simulation Problem
18511	DMOJ Mock CCC '18 Contest 1 J4/S2 - A Square Problem
18510	DMOJ Mock CCC '18 Contest 1 J3/S1 - A Math Problem
18509	DMOJ Mock CCC '18 Contest 1 J2 - A Substring Problem
18508	DMOJ Mock CCC '18 Contest 1 J1 - A String Problem
18507	DMOJ Mock CCC '22 2 S5 - Kaguya Wants to go Window Shopping with Kei Shirogane
18506	DMOJ Mock CCC '22 2 S4 - Kaguya Wants to Build a Great Wall
18505	DMOJ Mock CCC '22 2 S3 - Kaguya Wants to Analyze the Academy Anthem
18504	DMOJ Mock CCC '22 2 S2 - Kaguya Wants to Grow the Student Council
18503	DMOJ Mock CCC '22 2 S1 - Kaguya Wants to Let Ishigami Pass
18502	DMOJ ICPC NAQ 2016 L - Unusual Darts

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

18551

DMOJ Mock CCC '19 Contest 2 S1 - Tudor's Double Doors

18550

DMOJ Mock CCC '19 Contest 2 J5 - Tudor Drinks Even More Tea

18549

DMOJ Mock CCC '19 Contest 2 J4 - Tudor Buys Some Cheesecake

18548

DMOJ Mock CCC '19 Contest 2 J3 - Tudor Buys Some Tea

18547

DMOJ Mock CCC '19 Contest 2 J2 - Tudor Drinks Some More Tea

18546