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)
1701	Codeforces 386C: Diverse Substrings
1700	Codeforces 386B: Fly, freebies, fly!
1699	Codeforces 386A: Second-Price Auction
1698	Codeforces 385E: Bear in the Field
1697	Codeforces 385D: Bear and Floodlight
1696	Codeforces 385C: Bear and Prime Numbers
1695	Codeforces 385B: Bear and Strings
1694	Codeforces 385A: Bear and Raspberry
1693	Codeforces 384B: Multitasking
1692	Codeforces 384A: Coder
1691	Codeforces 383E: Vowels
1690	Codeforces 383D: Antimatter
1689	Codeforces 383C: Propagating tree
1688	Codeforces 383B: Volcanoes
1687	Codeforces 383A: Milking cows
1686	Codeforces 382E: Ksenia and Combinatorics
1685	Codeforces 382D: Ksenia and Pawns
1684	Codeforces 382C: Arithmetic Progression
1683	Codeforces 382B: Number Busters
1682	Codeforces 382A: Ksenia and Pan Scales
1681	Codeforces 381B: Sereja and Stairs
1680	Codeforces 381A: Sereja and Dima
1679	Codeforces 380E: Sereja and Dividing
1678	Codeforces 380D: Sereja and Cinema
1677	Codeforces 380C: Sereja and Brackets
1676	Codeforces 380B: Sereja and Tree
1675	Codeforces 380A: Sereja and Prefixes
1674	Codeforces 379G: New Year Cactus
1673	Codeforces 379F: New Year Tree
1672	Codeforces 379E: New Year Tree Decorations
1671	Codeforces 379D: New Year Letter
1670	Codeforces 379C: New Year Ratings Change
1669	Codeforces 379B: New Year Present
1668	Codeforces 379A: New Year Candles
1667	Codeforces 378B: Semifinals
1666	Codeforces 378A: Playing with Dice
1665	Codeforces 377E: Cookie Clicker
1664	Codeforces 377D: Developing Game
1663	Codeforces 377C: Captains Mode
1662	Codeforces 377B: Preparing for the Contest
1661	Codeforces 377A: Maze
1660	Codeforces 376B: I.O.U.
1659	Codeforces 376A: Lever
1658	Codeforces 375E: Red and Black Tree
1657	Codeforces 375D: Tree and Queries
1656	Codeforces 375C: Circling Round Treasures
1655	Codeforces 375B: Maximum Submatrix 2
1654	Codeforces 375A: Divisible by Seven
1653	Codeforces 374E: Inna and Babies
1652	Codeforces 374D: Inna and Sequence

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

1701

Codeforces 386C: Diverse Substrings

1700

Codeforces 386B: Fly, freebies, fly!

1699

Codeforces 386A: Second-Price Auction

1698

Codeforces 385E: Bear in the Field

1697

Codeforces 385D: Bear and Floodlight

1696