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)
12501	AtCoder JAG2013SUMMER-DAY3: C. Wave Attack
12500	AtCoder JAG2013SUMMER-DAY3: B. Minus One
12499	AtCoder JAG2013SUMMER-DAY3: A. Invest Master
12498	AtCoder JAG2013SUMMER-DAY2: G. Perm Query
12497	AtCoder JAG2013SUMMER-DAY2: F. Social Monsters
12496	AtCoder JAG2013SUMMER-DAY2: E. Pattern Language
12495	AtCoder JAG2013SUMMER-DAY2: D. TiMe Table
12494	AtCoder JAG2013SUMMER-DAY2: C. Apples
12493	AtCoder JAG2013SUMMER-DAY2: B. Evacuation Route
12492	AtCoder JAG2013SUMMER-DAY2: A. Koto Distance
12491	AtCoder JAG2013SPRING: J. Tree Reconstruction
12490	AtCoder JAG2013SPRING: I. The J-th Number
12489	AtCoder JAG2013SPRING: H. Rings
12488	AtCoder JAG2013SPRING: G. Revenge of Minimum Cost Flow
12487	AtCoder JAG2013SPRING: F. Point Distance
12486	AtCoder JAG2013SPRING: E. Minimum Spanning Tree
12485	AtCoder JAG2013SPRING: D. Medical Inspection
12484	AtCoder JAG2013SPRING: C. Iyasugigappa
12483	AtCoder JAG2013SPRING: B. Integer in Integer
12482	AtCoder JAG2013SPRING: A. Everlasting Zero
12481	AtCoder JAG2013AUTUMN: J. Magical Switches
12480	AtCoder JAG2013AUTUMN: I. Overwriting Game
12479	AtCoder JAG2013AUTUMN: H. Venn Diagram
12478	AtCoder JAG2013AUTUMN: G. Floating Islands
12477	AtCoder JAG2013AUTUMN: F. Shipura
12476	AtCoder JAG2013AUTUMN: E. Putter
12475	AtCoder JAG2013AUTUMN: D. Everlasting -One-
12474	AtCoder JAG2013AUTUMN: C. SIRO Challenge
12473	AtCoder JAG2013AUTUMN: B. Restore Calculation
12472	AtCoder JAG2013AUTUMN: A. Broken Audio Signal
12471	AtCoder JAG2012AUTUMN: J. Ancient Scrolls
12470	AtCoder JAG2012AUTUMN: I. Hashigo Sama
12469	AtCoder JAG2012AUTUMN: H. Magical Bridges
12468	AtCoder JAG2012AUTUMN: G. Ancient Commemorative Monolith
12467	AtCoder JAG2012AUTUMN: F. Counting 1's
12466	AtCoder JAG2012AUTUMN: E. Stack Maze
12465	AtCoder JAG2012AUTUMN: D. Billiard
12464	AtCoder JAG2012AUTUMN: C. Median Tree
12463	AtCoder JAG2012AUTUMN: B. Texas hold 'em
12462	AtCoder JAG2012AUTUMN: A. Dictionary
12461	AtCoder HOKUDAI-HITACHI2022: B. Dynamic Scheduling of Agricultural Machinery Sharing
12460	AtCoder HOKUDAI-HITACHI2022: A. Scheduling of Agricultural Machinery Sharing
12459	AtCoder HOKUDAI-HITACHI2021: B. Regional area design and daily operation
12458	AtCoder HOKUDAI-HITACHI2021: A. Regional area design
12457	AtCoder HOKUDAI-HITACHI2020: B. hokudai_hitachi2020_b
12456	AtCoder HOKUDAI-HITACHI2020: A. hokudai_hitachi2020_a
12455	AtCoder HOKUDAI-HITACHI2019-2: A. Problem C
12454	AtCoder HOKUDAI-HITACHI2019-1: B. Problem B
12453	AtCoder HOKUDAI-HITACHI2019-1: A. Problem A
12452	AtCoder HOKUDAI-HITACHI2018: C. Problem Setting C

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

12501

AtCoder JAG2013SUMMER-DAY3: C. Wave Attack

12500

AtCoder JAG2013SUMMER-DAY3: B. Minus One

12499

AtCoder JAG2013SUMMER-DAY3: A. Invest Master

12498

AtCoder JAG2013SUMMER-DAY2: G. Perm Query

12497

AtCoder JAG2013SUMMER-DAY2: F. Social Monsters

12496