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)
7001	Codeforces 1535A: Fair Playoff
7000	Codeforces 1534H: Lost Nodes
6999	Codeforces 1534G: A New Beginning
6998	Codeforces 1534F2: Falling Sand (Hard Version)
6997	Codeforces 1534F1: Falling Sand (Easy Version)
6996	Codeforces 1534E: Lost Array
6995	Codeforces 1534D: Lost Tree
6994	Codeforces 1534C: Little Alawn's Puzzle
6993	Codeforces 1534B: Histogram Ugliness
6992	Codeforces 1534A: Colour the Flag
6991	Codeforces 1533J: Pawns
6990	Codeforces 1533I: Excursions
6989	Codeforces 1533H: Submatrices
6988	Codeforces 1533G: Biome Map
6987	Codeforces 1533F: Binary String Partition
6986	Codeforces 1533E: Chess Team Forming
6985	Codeforces 1533D: String Searching
6984	Codeforces 1533C: Sweets
6983	Codeforces 1533B: Nearest Point Function
6982	Codeforces 1533A: Travel to Bertown
6981	Codeforces 1532F: Prefixes and Suffixes
6980	Codeforces 1532E: Good Array
6979	Codeforces 1532D: Teams Forming
6978	Codeforces 1532C: Uniform String
6977	Codeforces 1532B: Frog Jumping
6976	Codeforces 1532A: A+B (Trial Problem)
6975	Codeforces 1531E3: Сортировка слиянием
6974	Codeforces 1531E2: Сортировка слиянием
6973	Codeforces 1531E1: Сортировка слиянием
6972	Codeforces 1531D: Редактируем Зингер \| color
6971	Codeforces 1531C: Симметричный амфитеатр
6970	Codeforces 1531B2: Мониторинг
6969	Codeforces 1531B1: Мониторинг
6968	Codeforces 1531A: Зингер \| color
6967	Codeforces 1530H: Turing's Award
6966	Codeforces 1530G: What a Reversal
6965	Codeforces 1530F: Bingo
6964	Codeforces 1530E: Minimax
6963	Codeforces 1530D: Secret Santa
6962	Codeforces 1530C: Pursuit
6961	Codeforces 1530B: Putting Plates
6960	Codeforces 1530A: Binary Decimal
6959	Codeforces 1529B: Sifid and Strange Subsequences
6958	Codeforces 1529A: Eshag Loves Big Arrays
6957	Codeforces 1528F: AmShZ Farm
6956	Codeforces 1528E: Mashtali and Hagh Trees
6955	Codeforces 1528D: It's a bird! No, it's a plane! No, it's AaParsa!
6954	Codeforces 1528C: Trees of Tranquillity
6953	Codeforces 1528B: Kavi on Pairing Duty
6952	Codeforces 1528A: Parsa's Humongous Tree

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

7001

Codeforces 1535A: Fair Playoff

7000

Codeforces 1534H: Lost Nodes

6999

Codeforces 1534G: A New Beginning

6998

Codeforces 1534F2: Falling Sand (Hard Version)

6997

Codeforces 1534F1: Falling Sand (Easy Version)

6996