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)
10501	AtCoder ABC299: E. Nearest Black Vertex
10500	AtCoder ABC299: D. Find by Query
10499	AtCoder ABC299: C. Dango
10498	AtCoder ABC299: B. Trick Taking
10497	AtCoder ABC299: A. Treasure Chest
10496	AtCoder ABC298: Ex. Sum of Min of Length
10495	AtCoder ABC298: G. Strawberry War
10494	AtCoder ABC298: F. Rook Score
10493	AtCoder ABC298: E. Unfair Sugoroku
10492	AtCoder ABC298: D. Writing a Numeral
10491	AtCoder ABC298: C. Cards Query Problem
10490	AtCoder ABC298: B. Coloring Matrix
10489	AtCoder ABC298: A. Job Interview
10488	AtCoder ABC297: Ex. Diff Adjacent
10487	AtCoder ABC297: G. Constrained Nim 2
10486	AtCoder ABC297: F. Minimum Bounding Box 2
10485	AtCoder ABC297: E. Kth Takoyaki Set
10484	AtCoder ABC297: D. Count Subtractions
10483	AtCoder ABC297: C. PC on the Table
10482	AtCoder ABC297: B. chess960
10481	AtCoder ABC297: A. Double Click
10480	AtCoder ABC296: Ex. Unite
10479	AtCoder ABC296: G. Polygon and Points
10478	AtCoder ABC296: F. Simultaneous Swap
10477	AtCoder ABC296: E. Transition Game
10476	AtCoder ABC296: D. M<=ab
10475	AtCoder ABC296: C. Gap Existence
10474	AtCoder ABC296: B. Chessboard
10473	AtCoder ABC296: A. Alternately
10472	AtCoder ABC295: Ex. E or m
10471	AtCoder ABC295: G. Minimum Reachable City
10470	AtCoder ABC295: F. substr = S
10469	AtCoder ABC295: E. Kth Number
10468	AtCoder ABC295: D. Three Days Ago
10467	AtCoder ABC295: C. Socks
10466	AtCoder ABC295: B. Bombs
10465	AtCoder ABC295: A. Probably English
10464	AtCoder ABC294: Ex. K-Coloring
10463	AtCoder ABC294: G. Distance Queries on a Tree
10462	AtCoder ABC294: F. Sugar Water 2
10461	AtCoder ABC294: E. 2xN Grid
10460	AtCoder ABC294: D. Bank
10459	AtCoder ABC294: C. Merge Sequences
10458	AtCoder ABC294: B. ASCII Art
10457	AtCoder ABC294: A. Filter
10456	AtCoder ABC293: Ex. Optimal Path Decomposition
10455	AtCoder ABC293: G. Triple Index
10454	AtCoder ABC293: F. Zero or One
10453	AtCoder ABC293: E. Geometric Progression
10452	AtCoder ABC293: D. Tying Rope

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

10501

AtCoder ABC299: E. Nearest Black Vertex

10500

AtCoder ABC299: D. Find by Query

10499

AtCoder ABC299: C. Dango

10498

AtCoder ABC299: B. Trick Taking

10497

AtCoder ABC299: A. Treasure Chest

10496