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)
12551	AtCoder JAG2014SPRING: J. Unfair Game
12550	AtCoder JAG2014SPRING: I. Tokyo Olympics Center
12549	AtCoder JAG2014SPRING: H. RLE Replacement
12548	AtCoder JAG2014SPRING: G. Proportional Representation
12547	AtCoder JAG2014SPRING: F. Polygon Guards
12546	AtCoder JAG2014SPRING: E. Parentheses
12545	AtCoder JAG2014SPRING: D. LR
12544	AtCoder JAG2014SPRING: C. Decoding Ancient Messages
12543	AtCoder JAG2014SPRING: B. Cube Coloring
12542	AtCoder JAG2014SPRING: A. Breadth-First Search by Foxpower
12541	AtCoder JAG2014AUTUMN: K. Idempotent Filter
12540	AtCoder JAG2014AUTUMN: J. Website Tour
12539	AtCoder JAG2014AUTUMN: I. Color the Map Extreme
12538	AtCoder JAG2014AUTUMN: H. Points and Lines
12537	AtCoder JAG2014AUTUMN: G. Cookie Counter
12536	AtCoder JAG2014AUTUMN: F. Reverse a Road II
12535	AtCoder JAG2014AUTUMN: E. Square in Circles
12534	AtCoder JAG2014AUTUMN: D. Flowers
12533	AtCoder JAG2014AUTUMN: C. Speedrun
12532	AtCoder JAG2014AUTUMN: B. Unknown Switches
12531	AtCoder JAG2014AUTUMN: A. North North West
12530	AtCoder JAG2013SUMMER-WARMINGUP: J. Very Intellectual Card Game
12529	AtCoder JAG2013SUMMER-WARMINGUP: I. Topology
12528	AtCoder JAG2013SUMMER-WARMINGUP: H. Shuffling Machine
12527	AtCoder JAG2013SUMMER-WARMINGUP: G. Moving Points
12526	AtCoder JAG2013SUMMER-WARMINGUP: F. Maximum Segment XOR
12525	AtCoder JAG2013SUMMER-WARMINGUP: E. Magic Doors
12524	AtCoder JAG2013SUMMER-WARMINGUP: D. Graph Destruction
12523	AtCoder JAG2013SUMMER-WARMINGUP: C. Containers
12522	AtCoder JAG2013SUMMER-WARMINGUP: B. Cans of Toys
12521	AtCoder JAG2013SUMMER-WARMINGUP: A. Anime Master
12520	AtCoder JAG2013SUMMER-DAY4: J. Rotation Game
12519	AtCoder JAG2013SUMMER-DAY4: I. Multi Path Story
12518	AtCoder JAG2013SUMMER-DAY4: H. Gravity Point
12517	AtCoder JAG2013SUMMER-DAY4: G. Spotlight Movement
12516	AtCoder JAG2013SUMMER-DAY4: F. Graph Automata Player
12515	AtCoder JAG2013SUMMER-DAY4: E. Optimal alpha beta pruning
12514	AtCoder JAG2013SUMMER-DAY4: D. Removing Magical Tiles
12513	AtCoder JAG2013SUMMER-DAY4: C. Fox Observation
12512	AtCoder JAG2013SUMMER-DAY4: B. Trodden Cable
12511	AtCoder JAG2013SUMMER-DAY4: A. Thread Tree
12510	AtCoder JAG2013SUMMER-DAY3: K. Air Pollution
12509	AtCoder JAG2013SUMMER-DAY3: J. くるくるくるりん
12508	AtCoder JAG2013SUMMER-DAY3: I. A + B
12507	AtCoder JAG2013SUMMER-DAY3: L. 京都旅行
12506	AtCoder JAG2013SUMMER-DAY3: H. Almost Same Substring
12505	AtCoder JAG2013SUMMER-DAY3: G. Unordered Operators
12504	AtCoder JAG2013SUMMER-DAY3: F. Phutball
12503	AtCoder JAG2013SUMMER-DAY3: E. 順位付け
12502	AtCoder JAG2013SUMMER-DAY3: D. Fast Division

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

12551

AtCoder JAG2014SPRING: J. Unfair Game

12550

AtCoder JAG2014SPRING: I. Tokyo Olympics Center

12549

AtCoder JAG2014SPRING: H. RLE Replacement

12548

AtCoder JAG2014SPRING: G. Proportional Representation

12547

AtCoder JAG2014SPRING: F. Polygon Guards

12546