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)
10801	AtCoder AGC028: D. Chords
10800	AtCoder AGC028: C. Min Cost Cycle
10799	AtCoder AGC028: B. Removing Blocks
10798	AtCoder AGC028: A. Two Abbreviations
10797	AtCoder AGC027: F. Grafting
10796	AtCoder AGC027: E. ABBreviate
10795	AtCoder AGC027: D. Modulo Matrix
10794	AtCoder AGC027: C. ABland Yard
10793	AtCoder AGC027: B. Garbage Collector
10792	AtCoder AGC027: A. Candy Distribution Again
10791	AtCoder AGC026: F. Manju Game
10790	AtCoder AGC026: E. Synchronized Subsequence
10789	AtCoder AGC026: D. Histogram Coloring
10788	AtCoder AGC026: C. String Coloring
10787	AtCoder AGC026: B. rng_10s
10786	AtCoder AGC026: A. Colorful Slimes 2
10785	AtCoder AGC025: F. Addition and Andition
10784	AtCoder AGC025: E. Walking on a Tree
10783	AtCoder AGC025: D. Choosing Points
10782	AtCoder AGC025: C. Interval Game
10781	AtCoder AGC025: B. RGB Coloring
10780	AtCoder AGC025: A. Digits Sum
10779	AtCoder AGC024: F. Simple Subsequence Problem
10778	AtCoder AGC024: E. Sequence Growing Hard
10777	AtCoder AGC024: D. Isomorphism Freak
10776	AtCoder AGC024: C. Sequence Growing Easy
10775	AtCoder AGC024: B. Backfront
10774	AtCoder AGC024: A. Fairness
10773	AtCoder AGC023: F. 01 on Tree
10772	AtCoder AGC023: E. Inversions
10771	AtCoder AGC023: D. Go Home
10770	AtCoder AGC023: C. Painting Machines
10769	AtCoder AGC023: B. Find Symmetries
10768	AtCoder AGC023: A. Zero-Sum Ranges
10767	AtCoder AGC022: F. Checkers
10766	AtCoder AGC022: E. Median Replace
10765	AtCoder AGC022: D. Shopping
10764	AtCoder AGC022: C. Remainder Game
10763	AtCoder AGC022: B. GCD Sequence
10762	AtCoder AGC022: A. Diverse Word
10761	AtCoder AGC021: F. Trinity
10760	AtCoder AGC021: E. Ball Eat Chameleons
10759	AtCoder AGC021: D. Reversed LCS
10758	AtCoder AGC021: C. Tiling
10757	AtCoder AGC021: B. Holes
10756	AtCoder AGC021: A. Digit Sum 2
10755	AtCoder AGC020: F. Arcs on a Circle
10754	AtCoder AGC020: E. Encoding Subsets
10753	AtCoder AGC020: D. Min Max Repetition
10752	AtCoder AGC020: C. Median Sum

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

10801

AtCoder AGC028: D. Chords

10800

AtCoder AGC028: C. Min Cost Cycle

10799

AtCoder AGC028: B. Removing Blocks

10798

AtCoder AGC028: A. Two Abbreviations

10797

AtCoder AGC027: F. Grafting

10796