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)
10751	AtCoder AGC020: B. Ice Rink Game
10750	AtCoder AGC020: A. Move and Win
10749	AtCoder AGC019: F. Yes or No
10748	AtCoder AGC019: E. Shuffle and Swap
10747	AtCoder AGC019: D. Shift and Flip
10746	AtCoder AGC019: C. Fountain Walk
10745	AtCoder AGC019: B. Reverse and Compare
10744	AtCoder AGC019: A. Ice Tea Store
10743	AtCoder AGC018: F. Two Trees
10742	AtCoder AGC018: E. Sightseeing Plan
10741	AtCoder AGC018: D. Tree and Hamilton Path
10740	AtCoder AGC018: C. Coins
10739	AtCoder AGC018: B. Sports Festival
10738	AtCoder AGC018: A. Getting Difference
10737	AtCoder AGC017: F. Zigzag
10736	AtCoder AGC017: E. Jigsaw
10735	AtCoder AGC017: D. Game on Tree
10734	AtCoder AGC017: C. Snuke and Spells
10733	AtCoder AGC017: B. Moderate Differences
10732	AtCoder AGC017: A. Biscuits
10731	AtCoder AGC016: F. Games on DAG
10730	AtCoder AGC016: E. Poor Turkeys
10729	AtCoder AGC016: D. XOR Replace
10728	AtCoder AGC016: C. +/- Rectangle
10727	AtCoder AGC016: B. Colorful Hats
10726	AtCoder AGC016: A. Shrinking
10725	AtCoder AGC015: F. Kenus the Ancient Greek
10724	AtCoder AGC015: E. Mr.Aoki Incubator
10723	AtCoder AGC015: D. A or...or B Problem
10722	AtCoder AGC015: C. Nuske vs Phantom Thnook
10721	AtCoder AGC015: B. Evilator
10720	AtCoder AGC015: A. A+...+B Problem
10719	AtCoder AGC014: F. Strange Sorting
10718	AtCoder AGC014: E. Blue and Red Tree
10717	AtCoder AGC014: D. Black and White Tree
10716	AtCoder AGC014: C. Closed Rooms
10715	AtCoder AGC014: B. Unplanned Queries
10714	AtCoder AGC014: A. Cookie Exchanges
10713	AtCoder AGC013: F. Two Faced Cards
10712	AtCoder AGC013: E. Placing Squares
10711	AtCoder AGC013: D. Piling Up
10710	AtCoder AGC013: C. Ants on a Circle
10709	AtCoder AGC013: B. Hamiltonish Path
10708	AtCoder AGC013: A. Sorted Arrays
10707	AtCoder AGC012: F. Prefix Median
10706	AtCoder AGC012: E. Camel and Oases
10705	AtCoder AGC012: D. Colorful Balls
10704	AtCoder AGC012: C. Tautonym Puzzle
10703	AtCoder AGC012: B. Splatter Painting
10702	AtCoder AGC012: A. AtCoder Group Contest

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

10751

AtCoder AGC020: B. Ice Rink Game

10750

AtCoder AGC020: A. Move and Win

10749

AtCoder AGC019: F. Yes or No

10748

AtCoder AGC019: E. Shuffle and Swap

10747

AtCoder AGC019: D. Shift and Flip

10746