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)
11051	AtCoder APC001: E. Antennas on Tree
11050	AtCoder APC001: D. Forest
11049	AtCoder APC001: C. Vacant Seat
11048	AtCoder APC001: B. Two Arrays
11047	AtCoder APC001: A. Two Integers
11046	AtCoder AISING2020: F. Two Snuke
11045	AtCoder AISING2020: E. Camel Train
11044	AtCoder AISING2020: D. Anything Goes to Zero
11043	AtCoder AISING2020: C. XYZ Triplets
11042	AtCoder AISING2020: B. An Odd Problem
11041	AtCoder AISING2020: A. Number of Multiples
11040	AtCoder AISING2019: E. Attack to a Tree
11039	AtCoder AISING2019: D. Nearest Card Game
11038	AtCoder AISING2019: C. Alternating Path
11037	AtCoder AISING2019: B. Contests
11036	AtCoder AISING2019: A. Bulletin Board
11035	AtCoder AHC021: A. Pyramid Sorting
11034	AtCoder AHC020: A. Broadcasting
11033	AtCoder AHC019: A. Silhouette Block Puzzle Creation
11032	AtCoder AHC018: A. Excavation
11031	AtCoder AHC017: A. Road Repair
11030	AtCoder AHC016: A. Graphorean
11029	AtCoder AHC015: A. Halloween Candy
11028	AtCoder AHC014: A. RectJoin
11027	AtCoder AHC013: A. Server Room
11026	AtCoder AHC012: A. AtCoder 10th Anniversary
11025	AtCoder AHC011: A. Sliding Tree Puzzle
11024	AtCoder AHC010: A. Loop Lines
11023	AtCoder AHC009: A. Robust Memory of Commuting Routes
11022	AtCoder AHC008: A. Territory
11021	AtCoder AHC007: A. Online MST
11020	AtCoder AHC006: A. Food Delivery
11019	AtCoder AHC005: A. Patrolling
11018	AtCoder AHC004: A. Alien's Genome Assembly
11017	AtCoder AHC003: A. Shortest Path Queries
11016	AtCoder AHC002: A. Walking on Tiles
11015	AtCoder AHC001: A. AtCoder Ad
11014	AtCoder AGC064: F. No Permutations
11013	AtCoder AGC064: E. Cross Sum Construction
11012	AtCoder AGC064: D. Red and Blue Chips
11011	AtCoder AGC064: C. Erase and Divide Game
11010	AtCoder AGC064: B. Red and Blue Spanning Tree
11009	AtCoder AGC064: A. i i's
11008	AtCoder AGC063: F. Simultaneous Floor
11007	AtCoder AGC063: E. Child to Parent
11006	AtCoder AGC063: D. Many CRT
11005	AtCoder AGC063: C. Add Mod Operations
11004	AtCoder AGC063: B. Insert 1, 2, 3, ...
11003	AtCoder AGC063: A. Mex Game
11002	AtCoder AGC062: F. Preserve Distinct

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

11051

AtCoder APC001: E. Antennas on Tree

11050

AtCoder APC001: D. Forest

11049

AtCoder APC001: C. Vacant Seat

11048

AtCoder APC001: B. Two Arrays

11047

AtCoder APC001: A. Two Integers

11046