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)
6851	Codeforces 1510D: Digits
6850	Codeforces 1510C: Cactus Not Enough
6849	Codeforces 1510B: Button Lock
6848	Codeforces 1510A: ASCII Automata Art
6847	Codeforces 1509C: The Sports Festival
6846	Codeforces 1509B: TMT Document
6845	Codeforces 1509A: Average Height
6844	Codeforces 1508F: Optimal Encoding
6843	Codeforces 1508E: Tree Calendar
6842	Codeforces 1508D: Swap Pass
6841	Codeforces 1508C: Complete the MST
6840	Codeforces 1508B: Almost Sorted
6839	Codeforces 1508A: Binary Literature
6838	Codeforces 1506G: Maximize the Remaining String
6837	Codeforces 1506F: Triangular Paths
6836	Codeforces 1506E: Restoring the Permutation
6835	Codeforces 1506D: Epic Transformation
6834	Codeforces 1506C: Double-ended Strings
6833	Codeforces 1506B: Partial Replacement
6832	Codeforces 1506A: Strange Table
6831	Codeforces 1505I: Mysterious language again, seriously?
6830	Codeforces 1505H: L BREAK into program
6829	Codeforces 1505G: Encoded message
6828	Codeforces 1505F: Math
6827	Codeforces 1505E: Cakewalk
6826	Codeforces 1505D: Xenolith? Hippodrome?
6825	Codeforces 1505C: Fibonacci Words
6824	Codeforces 1505B: DMCA
6823	Codeforces 1505A: Is it rated - 2
6822	Codeforces 1504B: Flip the Bits
6821	Codeforces 1504A: Déjà Vu
6820	Codeforces 1503F: Balance the Cards
6819	Codeforces 1503E: 2-Coloring
6818	Codeforces 1503D: Flip the Cards
6817	Codeforces 1503C: Travelling Salesman Problem
6816	Codeforces 1503B: 3-Coloring
6815	Codeforces 1503A: Balance the Bits
6814	Codeforces 1501B: Napoleon Cake
6813	Codeforces 1501A: Alexey and Train
6812	Codeforces 1500F: Cupboards Jumps
6811	Codeforces 1500E: Subset Trick
6810	Codeforces 1500D: Tiles for Bathroom
6809	Codeforces 1500C: Matrix Sorting
6808	Codeforces 1500B: Two chandeliers
6807	Codeforces 1500A: Going Home
6806	Codeforces 1499G: Graph Coloring
6805	Codeforces 1499F: Diameter Cuts
6804	Codeforces 1499E: Chaotic Merge
6803	Codeforces 1499D: The Number of Pairs
6802	Codeforces 1499C: Minimum Grid Path

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

6851

Codeforces 1510D: Digits

6850

Codeforces 1510C: Cactus Not Enough

6849

Codeforces 1510B: Button Lock

6848

Codeforces 1510A: ASCII Automata Art

6847

Codeforces 1509C: The Sports Festival

6846