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)
15651	DMOJ CCC '11 S5 - Switch
15650	DMOJ CCC '11 S4 - Blood Distribution
15649	DMOJ CCC '11 S3 - Alice Through the Looking Glass
15648	DMOJ CCC '11 S2 - Multiple Choice
15647	DMOJ CCC '11 S1 - English or French?
15646	DMOJ CCC '11 J5 - Unfriend
15645	DMOJ CCC '11 J4 - Boring Business
15644	DMOJ CCC '11 J3 - Sumac Sequences
15643	DMOJ CCC '11 J2 - Who Has Seen The Wind
15642	DMOJ CCC '11 J1 - Which Alien?
15641	DMOJ CCC '10 S5 - Nutrient Tree
15640	DMOJ CCC '10 S4 - Animal Farm
15639	DMOJ CCC '10 S3 - Firehose
15638	DMOJ CCC '10 S2 - Huffman Encoding
15637	DMOJ CCC '10 S1 - Computer Purchase
15636	DMOJ CCC '10 J5 - Knight Hop
15635	DMOJ CCC '10 J4 - Global Warming
15634	DMOJ CCC '10 J3 - Punchy
15633	DMOJ CCC '10 J2 - Up and Down
15632	DMOJ CCC '10 J1 - What is n, Daddy?
15631	DMOJ CCC '09 S5 - Wireless
15630	DMOJ CCC '09 S4 - Shop and Ship
15629	DMOJ CCC '09 S3 - Degrees Of Separation
15628	DMOJ CCC '09 S2 - Lights Going On and Off
15627	DMOJ CCC '09 S1 - Cool Numbers
15626	DMOJ CCC '09 J4 - Signage
15625	DMOJ CCC '09 J3 - Good Times
15624	DMOJ CCC '09 J2 - Old Fishin' Hole
15623	DMOJ CCC '09 J1 - ISBN
15622	DMOJ CCC '08 S5 - Nukit
15621	DMOJ CCC '08 S4 - Twenty-four
15620	DMOJ CCC '08 S3 - Maze
15619	DMOJ CCC '08 S2 - Pennies in the Ring
15618	DMOJ CCC '08 S1 - It's Cold Here!
15617	DMOJ CCC '08 J4 - From Prefix to Postfix
15616	DMOJ CCC '08 J3 - GPS Text Entry
15615	DMOJ CCC '08 J2 - Do the Shuffle
15614	DMOJ CCC '08 J1 - Body Mass Index
15613	DMOJ CCC '07 S5 - Bowling for Numbers
15612	DMOJ CCC '07 S4 - Waterpark
15611	DMOJ CCC '07 S3 - Friends
15610	DMOJ CCC '07 S2 - Boxes
15609	DMOJ CCC '07 S1 - Federal Voting Age
15608	DMOJ CCC '07 J5 - Keep on Truckin'
15607	DMOJ CCC '07 J4 - Anagram Checker
15606	DMOJ CCC '07 J3 - Deal or No Deal Calculator
15605	DMOJ CCC '07 J2 - I Speak TXTMSG
15604	DMOJ CCC '07 J1 - Who is in the Middle?
15603	DMOJ CCC '06 S5 - Origin of Life
15602	DMOJ CCC '06 S4 - Groups

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

15651

DMOJ CCC '11 S5 - Switch

15650

DMOJ CCC '11 S4 - Blood Distribution

15649

DMOJ CCC '11 S3 - Alice Through the Looking Glass

15648

DMOJ CCC '11 S2 - Multiple Choice

15647

DMOJ CCC '11 S1 - English or French?

15646