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)
17551	DMOJ ECOO '15 R3 P2 - Tiling Trouble
17550	DMOJ ECOO '15 R3 P1 - Just the Factoradics, Ma'am
17549	DMOJ ECOO '15 R2 P4 - Rectangle Roundup
17548	DMOJ ECOO '15 R2 P3 - Lucas' Other Tower
17547	DMOJ ECOO '15 R2 P2 - So So
17546	DMOJ ECOO '15 R2 P1 - The Interlace Cypher
17545	DMOJ ECOO '15 R1 P4 - Neanderthal Numbers
17544	DMOJ ECOO '15 R1 P3 - Ten Pin Trig
17543	DMOJ ECOO '15 R1 P2 - Word Wrap
17542	DMOJ ECOO '15 R1 P1 - When You Eat Your Smarties
17541	DMOJ ECOO '14 R3 P4 - Baby Talk
17540	DMOJ ECOO '14 R3 P3 - Future City
17539	DMOJ ECOO '14 R3 P2 - Mothers and Daughters
17538	DMOJ ECOO '14 R3 P1 - Substitute Teacher
17537	DMOJ ECOO '14 R2 P4 - What Lies Ahead
17536	DMOJ ECOO '14 R2 P3 - EasySweeper
17535	DMOJ ECOO '14 R2 P2 - Black and Grey
17534	DMOJ ECOO '14 R2 P1 - Scratch and Win
17533	DMOJ ECOO '14 R1 P4 - Fischer Random Chess
17532	DMOJ ECOO '14 R1 P3 - Word Search
17531	DMOJ ECOO '14 R1 P2 - Orphan Black
17530	DMOJ ECOO '14 R1 P1 - Martian Time
17529	DMOJ ECOO '13 R3 P4 - Tour de Force
17528	DMOJ ECOO '13 R3 P3 - Go With the Flow
17527	DMOJ ECOO '13 R3 P2 - Mutant Children
17526	DMOJ ECOO '13 R3 P1 - Irregular Expressions
17525	DMOJ ECOO '13 R2 P4 - Breaking Rocks
17524	DMOJ ECOO '13 R2 P3 - Last Robot Standing
17523	DMOJ ECOO '13 R2 P2 - The Walking Dead
17522	DMOJ ECOO '13 R2 P1 - Upsetris
17521	DMOJ ECOO '13 R1 P4 - Coupon Day
17520	DMOJ ECOO '13 R1 P3 - Hexudoku
17519	DMOJ ECOO '13 R1 P2 - The Luhn Algorithm
17518	DMOJ ECOO '13 R1 P1 - Take a Number
17517	DMOJ ECOO '12 R3 P4 - Splitsville
17516	DMOJ ECOO '12 R3 P3 - Steam Arithmetic
17515	DMOJ ECOO '12 R3 P2 - Jewelry Tips
17514	DMOJ ECOO '12 R3 P1 - The Word Garden
17513	DMOJ ECOO '12 R2 P4 - Lo Shudoku
17512	DMOJ ECOO '12 R2 P3 - Airport Radar
17511	DMOJ ECOO '12 R2 P2 - Password Strength
17510	DMOJ ECOO '12 R2 P1 - Prime Time
17509	DMOJ ECOO '12 R1 P4 - Boggled
17508	DMOJ ECOO '12 R1 P3 - Triangles
17507	DMOJ ECOO '12 R1 P2 - Decoding DNA
17506	DMOJ ECOO '12 R1 P1 - Sluggers
17505	DMOJ ECOO '07 R3 P4 - Reverse Polish Logic
17504	DMOJ ECOO '07 R3 P1 - Sum of Primes
17503	DMOJ ICPC ECNA 2019 C - Cheese, If You Please
17502	DMOJ ICPC ECNA 2016 J - Yes, Yes, It's Nonograms

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

17551

DMOJ ECOO '15 R3 P2 - Tiling Trouble

17550

DMOJ ECOO '15 R3 P1 - Just the Factoradics, Ma'am

17549

DMOJ ECOO '15 R2 P4 - Rectangle Roundup

17548

DMOJ ECOO '15 R2 P3 - Lucas' Other Tower

17547

DMOJ ECOO '15 R2 P2 - So So

17546