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)
18451	DMOJ Monkey Country
18450	DMOJ Monkey Cards
18449	DMOJ Monkey Bread
18448	DMOJ Modulo Sort
18447	DMOJ Modular Multiplicative Inverse
18446	DMOJ Modern Art
18445	DMOJ Mocking SpongeBob
18444	DMOJ Mock ECOO '14 P1 - Do You Want to Build a Snowman?
18443	DMOJ Mock DWITE '09 P5 - Traffic Lights
18442	DMOJ Mock DWITE '09 P4 - Lights Out!
18441	DMOJ Mock DWITE '09 P3 - Trailing Bears!
18440	DMOJ Mock DWITE '09 P2 - The Missing Link...
18439	DMOJ Mock DWITE '09 P1 - Super Special Awesome Numbers =D
18438	DMOJ Mock CCC '15 S5 - Kongou
18437	DMOJ Mock CCC '15 S4 - Ice Pillars
18436	DMOJ Mock CCC '15 S3 - The Tachyon Trap
18435	DMOJ Mock CCC '15 S2 - Problem-setting Pandemonium
18434	DMOJ Mock CCC '15 S1 - Dupvoting
18433	DMOJ Mock CCC '15 J5 - Royal Guard
18432	DMOJ Mock CCC '15 J4 - Vox in Box
18431	DMOJ Mock CCC '15 J3 - Problem-setting Pandemonium
18430	DMOJ Mock CCC '15 J2 - Lowest Exam Mark
18429	DMOJ Mock CCC '15 J1 - 416
18428	DMOJ Mock CCC '14 S5 - Elimination Game
18427	DMOJ Mock CCC '14 S4 - Roadtrip Tracking
18426	DMOJ Mock CCC '14 S3 - Spreadsheet Sorting
18425	DMOJ Mock CCC '14 S2 - Sleep Cycle
18424	DMOJ Mock CCC '14 S1 - Reverse Find
18423	DMOJ Mock CCC '14 J5 - Spacetime Surfer
18422	DMOJ Mock CCC '14 J4 - Selecting Shifts
18421	DMOJ Mock CCC '14 J3 - Clock Hands
18420	DMOJ Mock CCC '14 J2 - Rope Unfolding
18419	DMOJ Mock CCC '14 J1 - Love Overdose
18418	DMOJ MNYC '17: Bells
18417	DMOJ MNYC '17: Skiing Competition
18416	DMOJ MNYC '17: Removing Christmas Trees
18415	DMOJ MNYC '17: Hurontario
18414	DMOJ MNYC '17: ASCII Art II
18413	DMOJ MNYC '17: 2048
18412	DMOJ MNYC '16: Rocks
18411	DMOJ MNYC '16: Jelly
18410	DMOJ MNYC '16: Abdoof
18409	DMOJ MNYC '16: ECOO!
18408	DMOJ MNYC '16: Moore's Law
18407	DMOJ MNYC '16: King Modulus
18406	DMOJ MMM '14 H - Lift Control
18405	DMOJ MMM '14 G - Campfire Cooking
18404	DMOJ MMM '14 F - Electricity Grid
18403	DMOJ MMM '14 E - English Essay
18402	DMOJ MMM '14 D - Kuuhaku Numbers

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

18451

18450

18449

18448

18447

DMOJ Modular Multiplicative Inverse

18446