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)
8301	Codeforces 1770D: Koxia and Game
8300	Codeforces 1770C: Koxia and Number Theory
8299	Codeforces 1770B: Koxia and Permutation
8298	Codeforces 1770A: Koxia and Whiteboards
8297	Codeforces 1769D3: Игра в Девятку III
8296	Codeforces 1769D2: Игра в Девятку II
8295	Codeforces 1769D1: Игра в Девятку I
8294	Codeforces 1769C2: Подкрутка II
8293	Codeforces 1769C1: Подкрутка I
8292	Codeforces 1769B2: Копирование файлов II
8291	Codeforces 1769B1: Копирование файлов I
8290	Codeforces 1769A: Узкая дорога
8289	Codeforces 1768F: Wonderful Jump
8288	Codeforces 1768E: Partial Sorting
8287	Codeforces 1768D: Lucky Permutation
8286	Codeforces 1768C: Elemental Decompress
8285	Codeforces 1768B: Quick Sort
8284	Codeforces 1768A: Greatest Convex
8283	Codeforces 1767F: Two Subtrees
8282	Codeforces 1767E: Algebra Flash
8281	Codeforces 1767D: Playoff
8280	Codeforces 1767C: Count Binary Strings
8279	Codeforces 1767B: Block Towers
8278	Codeforces 1767A: Cut the Triangle
8277	Codeforces 1766F: MCF
8276	Codeforces 1766E: Decomposition
8275	Codeforces 1766D: Lucky Chains
8274	Codeforces 1766C: Hamiltonian Wall
8273	Codeforces 1766B: Notepad#
8272	Codeforces 1766A: Extremely Round
8271	Codeforces 1765N: Number Reduction
8270	Codeforces 1765M: Minimum LCM
8269	Codeforces 1765L: Project Manager
8268	Codeforces 1765K: Torus Path
8267	Codeforces 1765J: Hero to Zero
8266	Codeforces 1765I: Infinite Chess
8265	Codeforces 1765H: Hospital Queue
8264	Codeforces 1765G: Guess the String
8263	Codeforces 1765F: Chemistry Lab
8262	Codeforces 1765E: Exchange
8261	Codeforces 1765D: Watch the Videos
8260	Codeforces 1765C: Card Guessing
8259	Codeforces 1765B: Broken Keyboard
8258	Codeforces 1765A: Access Levels
8257	Codeforces 1764H: Doremy's Paint 2
8256	Codeforces 1764G3: Doremy's Perfect DS Class (Hard Version)
8255	Codeforces 1764G2: Doremy's Perfect DS Class (Medium Version)
8254	Codeforces 1764G1: Doremy's Perfect DS Class (Easy Version)
8253	Codeforces 1764F: Doremy's Experimental Tree
8252	Codeforces 1764E: Doremy's Number Line

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

8301

Codeforces 1770D: Koxia and Game

8300

Codeforces 1770C: Koxia and Number Theory

8299

Codeforces 1770B: Koxia and Permutation

8298

Codeforces 1770A: Koxia and Whiteboards

8297

Codeforces 1769D3: Игра в Девятку III

8296