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)
23851	AtCoder ABC317: B. MissingNo.
23850	AtCoder ABC317: A. Potions
23849	Codeforces 1864I: Future Dominators
23848	Codeforces 1864H: Asterism Stream
23847	Codeforces 1864G: Magic Square
23846	Codeforces 1864F: Exotic Queries
23845	Codeforces 1864E: Guess Game
23844	Codeforces 1864D: Matrix Cascade
23843	Codeforces 1864C: Divisor Chain
23842	Codeforces 1864B: Swap and Reverse
23841	Codeforces 1864A: Increasing and Decreasing
23840	AtCoder EDITOR-UPDATE-TEST: B. 部分木サイズ
23839	AtCoder EDITOR-UPDATE-TEST: A. Ax+By
23838	Codeforces 1862G: The Great Equalizer
23837	Codeforces 1862F: Magic Will Save the World
23836	Codeforces 1862E: Kolya and Movie Theatre
23835	Codeforces 1862D: Ice Cream Balls
23834	Codeforces 1862C: Flower City Fence
23833	Codeforces 1862B: Sequence Game
23832	Codeforces 1862A: Gift Carpet
23831	DMOJ NOI '22 P6 - Quadratic Integer Program
23830	DMOJ NOI '22 P5 - Bubble Sort
23829	DMOJ NOI '22 P4 - Challenge NPC
23828	DMOJ NOI '22 P3 - Count
23827	AtCoder AHC022: A. Exploring Another Space
23826	AtCoder ABC315: Ex. Typical Convolution Problem
23825	AtCoder ABC315: G. Ai + Bj + Ck = X (1 <= i, j, k <= N)
23824	AtCoder ABC315: F. Shortcuts
23823	AtCoder ABC315: E. Prerequisites
23822	AtCoder ABC315: D. Magical Cookies
23821	AtCoder ABC315: C. Flavors
23820	AtCoder ABC315: B. The Middle Day
23819	AtCoder ABC315: A. tcdr
23818	DMOJ Yet Another Contest 7 P6 - Arithmetic Sequence Data Structure
23817	DMOJ Yet Another Contest 7 P5 - Egg Dropping
23816	DMOJ Yet Another Contest 7 P4 - Paparazzi
23815	DMOJ Yet Another Contest 7 P3 - No More Math Homework
23814	DMOJ Yet Another Contest 7 P2 - Coprime Grid
23813	DMOJ Yet Another Contest 7 P1 - Page Turning
23812	Codeforces 1860F: Evaluate RBS
23811	Codeforces 1860E: Fast Travel Text Editor
23810	Codeforces 1860D: Balanced String
23809	Codeforces 1860C: Game on Permutation
23808	Codeforces 1860B: Fancy Coins
23807	Codeforces 1860A: Not a Substring
23806	DMOJ NOIP '08 P3 - Message Passing
23805	DMOJ NOIP '08 P2 - Expression by Matches
23804	DMOJ NOIP '08 P1 - Silly Monkey
23803	DMOJ NOIP '07 P4 - Core of a Tree Net
23802	DMOJ NOIP '07 P3 - Removing Numbers from Matrix

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

23851

AtCoder ABC317: B. MissingNo.

23850

AtCoder ABC317: A. Potions

23849

Codeforces 1864I: Future Dominators

23848

Codeforces 1864H: Asterism Stream

23847

Codeforces 1864G: Magic Square

23846