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)
10851	AtCoder AGC036: E. ABC String
10850	AtCoder AGC036: D. Negative Cycle
10849	AtCoder AGC036: C. GP 2
10848	AtCoder AGC036: B. Do Not Duplicate
10847	AtCoder AGC036: A. Triangle
10846	AtCoder AGC035: F. Two Histograms
10845	AtCoder AGC035: E. Develop
10844	AtCoder AGC035: D. Add and Remove
10843	AtCoder AGC035: C. Skolem XOR Tree
10842	AtCoder AGC035: B. Even Degrees
10841	AtCoder AGC035: A. XOR Circle
10840	AtCoder AGC034: F. RNG and XOR
10839	AtCoder AGC034: E. Complete Compress
10838	AtCoder AGC034: D. Manhattan Max Matching
10837	AtCoder AGC034: C. Tests
10836	AtCoder AGC034: B. ABC
10835	AtCoder AGC034: A. Kenken Race
10834	AtCoder AGC033: F. Adding Edges
10833	AtCoder AGC033: E. Go around a Circle
10832	AtCoder AGC033: D. Complexity
10831	AtCoder AGC033: C. Removing Coins
10830	AtCoder AGC033: B. LRUD Game
10829	AtCoder AGC033: A. Darker and Darker
10828	AtCoder AGC032: F. One Third
10827	AtCoder AGC032: E. Modulo Pairing
10826	AtCoder AGC032: D. Rotation Sort
10825	AtCoder AGC032: C. Three Circuits
10824	AtCoder AGC032: B. Balanced Neighbors
10823	AtCoder AGC032: A. Limited Insertion
10822	AtCoder AGC031: F. Walk on Graph
10821	AtCoder AGC031: E. Snuke the Phantom Thief
10820	AtCoder AGC031: D. A Sequence of Permutations
10819	AtCoder AGC031: C. Differ by 1 Bit
10818	AtCoder AGC031: B. Reversi
10817	AtCoder AGC031: A. Colorful Subsequence
10816	AtCoder AGC030: F. Permutation and Minimum
10815	AtCoder AGC030: E. Less than 3
10814	AtCoder AGC030: D. Inversion Sum
10813	AtCoder AGC030: C. Coloring Torus
10812	AtCoder AGC030: B. Tree Burning
10811	AtCoder AGC030: A. Poisonous Cookies
10810	AtCoder AGC029: F. Construction of a tree
10809	AtCoder AGC029: E. Wandering TKHS
10808	AtCoder AGC029: D. Grid game
10807	AtCoder AGC029: C. Lexicographic constraints
10806	AtCoder AGC029: B. Powers of two
10805	AtCoder AGC029: A. Irreversible operation
10804	AtCoder AGC028: F2. Reachable Cells
10803	AtCoder AGC028: F. Reachable Cells
10802	AtCoder AGC028: E. High Elements

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

10851

AtCoder AGC036: E. ABC String

10850

AtCoder AGC036: D. Negative Cycle

10849

AtCoder AGC036: C. GP 2

10848

AtCoder AGC036: B. Do Not Duplicate

10847

AtCoder AGC036: A. Triangle

10846