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)
19751	DMOJ XOR
19750	DMOJ A Very Coordinated Christmas
19749	DMOJ William and Summation
19748	DMOJ WOSS Dual Olympiad 2022 Team Round P3: Bobby and the Sidewalk
19747	DMOJ WOSS Dual Olympiad 2022 Team Round P2: Bobby's Studying Schedule
19746	DMOJ WOSS Dual Olympiad 2022 Team Round P1: Bobby and His Calculus Test
19745	DMOJ WOSS Dual Olympiad 2022 S3: Sightseeing in the North Pole
19744	DMOJ WOSS Dual Olympiad 2022 S2: Festive Card Game
19743	DMOJ WOSS Dual Olympiad 2022 J4: Fire on Christmas Day
19742	DMOJ WOSS Dual Olympiad 2022 J3/S1: Christmas List
19741	DMOJ WOSS Dual Olympiad 2022 J2: Counting Christmas Trees
19740	DMOJ WOSS Dual Olympiad 2022 J1: Holiday Gifting
19739	DMOJ WOSS Dual Olympiad 2021 S3: Late for Class!
19738	DMOJ WOSS Dual Olympiad 2021 J3: Frisbee Golf
19737	DMOJ WOSS Dual Olympiad 2021 J2/S1: Secret Formula
19736	DMOJ WOSS Dual Olympiad 2021 J1: Water Classification
19735	DMOJ World Tour Contest Problem 4 — W Szczebrzeszynie chrząszcz brzmi w trzcinie
19734	DMOJ World Tour Contest Problem 3 — Translation
19733	DMOJ World Tour Contest Problem 2 — Fireplace Poker
19732	DMOJ World Tour Contest Problem 1 — Solar Eclipse
19731	DMOJ Word Wrap Cypher
19730	DMOJ Guess the Wordle
19729	DMOJ Word Counting
19728	DMOJ Willie's Fan Club
19727	DMOJ When GCD meets XOR
19726	DMOJ ACM-ICPC World Finals 2007 Problem J - Tunnels
19725	DMOJ Wesley++
19724	DMOJ WC '99 Suicidal P6 - Wedding Juicer
19723	DMOJ WC '99 Suicidal P5 - Star Wars
19722	DMOJ WC '99 Suicidal P4 - Good Ethan Hunt
19721	DMOJ WC '99 Suicidal P3 - Message
19720	DMOJ WC '99 Suicidal P2 - Good Hunting Will
19719	DMOJ WC '99 Suicidal P1 - World
19718	DMOJ WC '99 P7 - The Rock
19717	DMOJ WC '99 P6 - Fight Club
19716	DMOJ WC '99 P5 - Good Will Hunting
19715	DMOJ WC '99 P4 - Goldfinger
19714	DMOJ WC '99 P3 - The Godfather
19713	DMOJ WC '99 P2 - Mission Impossible
19712	DMOJ WC '99 P1 - The Matrix
19711	DMOJ WC '98 P6 - Return of the Plachta
19710	DMOJ WC '98 P5 - Y2K
19709	DMOJ WC '98 P4 - GATTACA
19708	DMOJ WC '98 P3 - Do or Do Not
19707	DMOJ WC '98 P2 - The Hutts Strike Back
19706	DMOJ WC '98 P1 - Optical Recognition
19705	DMOJ WC '97 P5 - Encoding Grid
19704	DMOJ WC '97 P4 - Typing
19703	DMOJ WC '97 P3 - Stacks of Flapjacks
19702	DMOJ WC '97 P2 - Power of Cryptography

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

19751

DMOJ XOR

19750

DMOJ A Very Coordinated Christmas

19749

DMOJ William and Summation

19748

DMOJ WOSS Dual Olympiad 2022 Team Round P3: Bobby and the Sidewalk

19747

DMOJ WOSS Dual Olympiad 2022 Team Round P2: Bobby's Studying Schedule

19746