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)
9151	AtCoder ABC085: A. Already 2018
9150	AtCoder ABC084: D. 2017-like Number
9149	AtCoder ABC084: C. Special Trains
9148	AtCoder ABC084: B. Postal Code
9147	AtCoder ABC084: A. New Year
9146	AtCoder ABC083: B. Some Sums
9145	AtCoder ABC083: A. Libra
9144	AtCoder ABC082: B. Two Anagrams
9143	AtCoder ABC082: A. Round Up the Mean
9142	AtCoder ABC081: B. Shift only
9141	AtCoder ABC081: A. Placing Marbles
9140	AtCoder ABC080: D. Recording
9139	AtCoder ABC080: C. Shopping Street
9138	AtCoder ABC080: B. Harshad Number
9137	AtCoder ABC080: A. Parking
9136	AtCoder ABC079: D. Wall
9135	AtCoder ABC079: C. Train Ticket
9134	AtCoder ABC079: B. Lucas Number
9133	AtCoder ABC079: A. Good Integer
9132	AtCoder ABC078: B. ISU
9131	AtCoder ABC078: A. HEX
9130	AtCoder ABC077: B. Around Square
9129	AtCoder ABC077: A. Rotation
9128	AtCoder ABC076: D. AtCoder Express
9127	AtCoder ABC076: C. Dubious Document 2
9126	AtCoder ABC076: B. Addition and Multiplication
9125	AtCoder ABC076: A. Rating Goal
9124	AtCoder ABC075: D. Axis-Parallel Rectangle
9123	AtCoder ABC075: C. Bridge
9122	AtCoder ABC075: B. Minesweeper
9121	AtCoder ABC075: A. One out of Three
9120	AtCoder ABC074: B. Collecting Balls (Easy Version)
9119	AtCoder ABC074: A. Bichrome Cells
9118	AtCoder ABC073: D. joisino's travel
9117	AtCoder ABC073: C. Write and Erase
9116	AtCoder ABC073: B. Theater
9115	AtCoder ABC073: A. September 9
9114	AtCoder ABC072: B. OddString
9113	AtCoder ABC072: A. Sandglass2
9112	AtCoder ABC071: B. Not Found
9111	AtCoder ABC071: A. Meal Delivery
9110	AtCoder ABC070: D. Transit Tree Path
9109	AtCoder ABC070: C. Multiple Clocks
9108	AtCoder ABC070: B. Two Switches
9107	AtCoder ABC070: A. Palindromic Number
9106	AtCoder ABC069: B. i18n
9105	AtCoder ABC069: A. K-City
9104	AtCoder ABC068: B. Break Number
9103	AtCoder ABC068: A. ABCxxx
9102	AtCoder ABC067: B. Snake Toy

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

9151

AtCoder ABC085: A. Already 2018

9150

AtCoder ABC084: D. 2017-like Number

9149

AtCoder ABC084: C. Special Trains

9148

AtCoder ABC084: B. Postal Code

9147

AtCoder ABC084: A. New Year

9146