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)
17501	DMOJ ICPC ECNA 2016 I - Waif Until Dark
17500	DMOJ ICPC ECNA 2016 H - Vin Diagrams
17499	DMOJ ICPC ECNA 2016 G - That's One Hanoi-ed Teacher
17498	DMOJ ICPC ECNA 2016 F - Removal Game
17497	DMOJ ICPC ECNA 2016 E - Red Rover
17496	DMOJ ICPC ECNA 2016 D - Lost in Translation
17495	DMOJ ICPC ECNA 2016 C - The Key to Cryptography
17494	DMOJ ICPC ECNA 2016 B - Foosball Dynasty
17493	DMOJ ICPC ECNA 2016 A - Bubbly Troubly
17492	DMOJ ICPC ECNA 2005 H - Two Ends
17491	DMOJ ICPC ECNA 2005 G - Swamp Things
17490	DMOJ ICPC ECNA 2005 F - Square Count
17489	DMOJ ICPC ECNA 2005 E - Reliable Nets
17488	DMOJ ICPC ECNA 2005 D - Queens, Knights and Pawns
17487	DMOJ ICPC ECNA 2005 C - The Game of Efil
17486	DMOJ ICPC ECNA 2005 B - Countdown
17485	DMOJ ICPC ECNA 2005 A - ACM (ACronym Maker)
17484	DMOJ ICPC ECNA 2000 F - To Bet or Not To Bet
17483	DMOJ ICPC ECNA 2000 E - Checker's Check
17482	DMOJ ICPC ECNA 2000 D - Stacking Cubes
17481	DMOJ ICPC ECNA 2000 C - Rational Approximation
17480	DMOJ ICPC ECNA 2000 B - Poly-polygonal Numbers
17479	DMOJ ICPC ECNA 2000 A - Picnic Planning
17478	DMOJ Dynamic Sum
17477	DMOJ DWITE '12 R5 #5 - Pattern Lock
17476	DMOJ DWITE '12 R5 #4 - Fencing Problems
17475	DMOJ DWITE '12 R5 #3 - Triangle Count
17474	DMOJ DWITE '12 R5 #2 - Copycat SMS
17473	DMOJ DWITE '12 R5 #1 - Travel Time
17472	DMOJ DWITE '12 R2 #5 - Car Hoppers
17471	DMOJ DWITE '12 R2 #4 - Magic Trick
17470	DMOJ DWITE '12 R2 #3 - Bitstrings
17469	DMOJ DWITE '12 R2 #2 - Word Arithmetic
17468	DMOJ DWITE '12 R2 #1 - Sugar Rush
17467	DMOJ DWITE '12 R1 #5 - Haunted House
17466	DMOJ DWITE '12 R1 #4 - Trick or Tree'ing
17465	DMOJ DWITE '12 R1 #3 - Costume Party
17464	DMOJ DWITE '12 R1 #2 - Candybar Graphs
17463	DMOJ DWITE '12 R1 #1 - Candy Piles
17462	DMOJ DWITE '11 R5 #5 - Binary Weight
17461	DMOJ DWITE '11 R5 #4 - Cube World
17460	DMOJ DWITE '11 R5 #3 - Unit rectangles
17459	DMOJ DWITE '11 R5 #2 - Forest Fires
17458	DMOJ DWITE '11 R5 #1 - Age Gate
17457	DMOJ DWITE '11 R4 #5 - Comet Vomit
17456	DMOJ DWITE '11 R4 #4 - Lego Ladder
17455	DMOJ DWITE '11 R4 #3 - Breaking Bonds
17454	DMOJ DWITE '11 R4 #2 - Prime Time
17453	DMOJ DWITE '11 R4 #1 - Crossword Count
17452	DMOJ DWITE '11 R3 #5 - Tautology

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

17501

DMOJ ICPC ECNA 2016 I - Waif Until Dark

17500

DMOJ ICPC ECNA 2016 H - Vin Diagrams

17499

DMOJ ICPC ECNA 2016 G - That's One Hanoi-ed Teacher

17498

DMOJ ICPC ECNA 2016 F - Removal Game

17497

DMOJ ICPC ECNA 2016 E - Red Rover

17496