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)
24871	USACO 2024 January Contest, Bronze: Balancing Bacteria
24870	USACO 2024 January Contest, Bronze: Cannonball
24869	USACO 2024 January Contest, Bronze: Majority Opinion
24868	USACO 2024 January Contest, Silver: Cowlendar
24867	USACO 2024 January Contest, Silver: Potion Farming
24866	USACO 2024 January Contest, Silver: Cowmpetency
24865	USACO 2024 January Contest, Gold: Nap Sort
24864	USACO 2024 January Contest, Gold: Cowmpetency
24863	USACO 2024 January Contest, Gold: Walking in Manhattan
24862	USACO 2024 January Contest, Platinum: Mooball Teams III
24861	USACO 2024 January Contest, Platinum: Merging Cells
24860	USACO 2024 January Contest, Platinum: Island Vacation
24859	DMOJ HHPC1 P1 - Yielding the Longest Substring
24858	DMOJ Yet Another Contest 8 P4 - Fluke 2
24857	DMOJ Yet Another Contest 8 P6 - Into the Woods
24856	DMOJ Yet Another Contest 8 P3 - Herobrine
24855	DMOJ HHPC1 P2 - Yuniformity Challenge
24854	DMOJ HHPC1 P5 - Yunity Grouping Objects
24853	DMOJ HHPC1 P3 - Yonder Ridge
24852	DMOJ HHPC1 P6 - Yarn Street's Strategic Shopping
24851	DMOJ HHPC1 P4 - Yet Another A+B Problem
24850	DMOJ Yet Another Contest 8 P2 - No More Modern Art
24849	DMOJ Yet Another Contest 8 P1 - Permutation Sorting
24848	DMOJ Yet Another Contest 8 P5 - Hidden Tree
24847	AtCoder JOI2024HO: E. 道路網の整備 2 (Road Service 2)
24846	AtCoder JOI2024HO: D. プレゼント交換 (Gift Exchange)
24845	AtCoder JOI2024HO: C. マラソン大会 2 (Marathon Race 2)
24844	AtCoder JOI2024HO: B. 建設事業 2 (Construction Project 2)
24843	AtCoder JOI2024HO: A. 室温 (Room Temperature)
24842	AtCoder ARC171: F. Both Reversible
24841	AtCoder ARC171: E. Rookhopper's Tour
24840	AtCoder ARC171: D. Rolling Hash
24839	AtCoder ARC171: C. Swap on Tree
24838	AtCoder ARC171: B. Chmax
24837	AtCoder ARC171: A. No Attacking
24836	AtCoder ABC340: G. Leaf Color
24835	AtCoder ABC340: F. S = 1
24834	AtCoder ABC340: E. Mancala 2
24833	AtCoder ABC340: D. Super Takahashi Bros.
24832	AtCoder ABC340: C. Divide and Divide
24831	AtCoder ABC340: B. Append
24830	AtCoder ABC340: A. Arithmetic Progression
24829	AtCoder ABC339: G. Smaller Sum
24828	AtCoder ABC339: F. Product Equality
24827	AtCoder ABC339: E. Smooth Subsequence
24826	AtCoder ABC339: D. Synchronized Players
24825	AtCoder ABC339: C. Perfect Bus
24824	AtCoder ABC339: B. Langton's Takahashi
24823	AtCoder ABC339: A. TLD
24822	Codeforces 1927G: Paint Charges

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

24871

USACO 2024 January Contest, Bronze: Balancing Bacteria

24870

USACO 2024 January Contest, Bronze: Cannonball

24869

USACO 2024 January Contest, Bronze: Majority Opinion

24868

USACO 2024 January Contest, Silver: Cowlendar

24867

USACO 2024 January Contest, Silver: Potion Farming

24866