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)
1801	Codeforces 409H: A + B Strikes Back
1800	Codeforces 409G: On a plane
1799	Codeforces 409F: 000001
1798	Codeforces 409E: Dome
1797	Codeforces 409D: Big Data
1796	Codeforces 409C: Magnum Opus
1795	Codeforces 409B: Mysterious Language
1794	Codeforces 409A: The Great Game
1793	Codeforces 408B: Garland
1792	Codeforces 408A: Line to Cashier
1791	Codeforces 407E: k-d-sequence
1790	Codeforces 407D: Largest Submatrix 3
1789	Codeforces 407C: Curious Array
1788	Codeforces 407B: Long Path
1787	Codeforces 407A: Triangle
1786	Codeforces 406E: Hamming Triples
1785	Codeforces 406D: Hill Climbing
1784	Codeforces 405E: Graph Cutting
1783	Codeforces 405D: Toy Sum
1782	Codeforces 405C: Unusual Product
1781	Codeforces 405B: Domino Effect
1780	Codeforces 405A: Gravity Flip
1779	Codeforces 404E: Maze 1D
1778	Codeforces 404D: Minesweeper 1D
1777	Codeforces 404C: Restore Graph
1776	Codeforces 404B: Marathon
1775	Codeforces 404A: Valera and X
1774	Codeforces 403E: Two Rooted Trees
1773	Codeforces 403D: Beautiful Pairs of Numbers
1772	Codeforces 402E: Strictly Positive Matrix
1771	Codeforces 402D: Upgrading Array
1770	Codeforces 402C: Searching for Graph
1769	Codeforces 402B: Trees in a Row
1768	Codeforces 402A: Nuts
1767	Codeforces 401E: Olympic Games
1766	Codeforces 401D: Roman and Numbers
1765	Codeforces 401C: Team
1764	Codeforces 401B: Sereja and Contests
1763	Codeforces 401A: Vanya and Cards
1762	Codeforces 400E: Inna and Binary Logic
1761	Codeforces 400D: Dima and Bacteria
1760	Codeforces 400C: Inna and Huge Candy Matrix
1759	Codeforces 400B: Inna and New Matrix of Candies
1758	Codeforces 400A: Inna and Choose Options
1757	Codeforces 399B: Red and Blue Balls
1756	Codeforces 399A: Pages
1755	Codeforces 398E: Sorting Permutations
1754	Codeforces 398D: Instant Messanger
1753	Codeforces 398C: Tree and Array
1752	Codeforces 398B: Painting The Wall

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

1801

Codeforces 409H: A + B Strikes Back

1800

Codeforces 409G: On a plane

1799

Codeforces 409F: 000001

1798

Codeforces 409E: Dome

1797

Codeforces 409D: Big Data

1796