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)
9101	AtCoder ABC067: A. Sharing Cookies
9100	AtCoder ABC066: B. ss
9099	AtCoder ABC066: A. ringring
9098	AtCoder ABC065: B. Trained?
9097	AtCoder ABC065: A. Expired?
9096	AtCoder ABC064: D. Insertion
9095	AtCoder ABC064: C. Colorful Leaderboard
9094	AtCoder ABC064: B. Traveling AtCoDeer Problem
9093	AtCoder ABC064: A. RGB Cards
9092	AtCoder ABC063: B. Varied
9091	AtCoder ABC063: A. Restricted
9090	AtCoder ABC062: B. Picture Frame
9089	AtCoder ABC062: A. Grouping
9088	AtCoder ABC061: D. Score Attack
9087	AtCoder ABC061: C. Big Array
9086	AtCoder ABC061: B. Counting Roads
9085	AtCoder ABC061: A. Between Two Integers
9084	AtCoder ABC060: B. Choose Integers
9083	AtCoder ABC060: A. Shiritori
9082	AtCoder ABC059: B. Comparison
9081	AtCoder ABC059: A. Three-letter acronym
9080	AtCoder ABC058: B. ∵∴∵
9079	AtCoder ABC058: A. ι⊥l
9078	AtCoder ABC057: D. Maximum Average Sets
9077	AtCoder ABC057: C. Digits in Multiplication
9076	AtCoder ABC057: B. Checkpoints
9075	AtCoder ABC057: A. Remaining Time
9074	AtCoder ABC056: B. NarrowRectanglesEasy
9073	AtCoder ABC056: A. HonestOrDishonest
9072	AtCoder ABC055: B. Training Camp
9071	AtCoder ABC055: A. Restaurant
9070	AtCoder ABC054: D. Mixing Experiment
9069	AtCoder ABC054: C. One-stroke Path
9068	AtCoder ABC054: B. Template Matching
9067	AtCoder ABC054: A. One Card Poker
9066	AtCoder ABC053: B. A to Z String
9065	AtCoder ABC053: A. ABC/ARC
9064	AtCoder ABC052: B. Increment Decrement
9063	AtCoder ABC052: A. Two Rectangles
9062	AtCoder ABC051: D. Candidates of No Shortest Paths
9061	AtCoder ABC051: C. Back and Forth
9060	AtCoder ABC051: B. Sum of Three Integers
9059	AtCoder ABC051: A. Haiku
9058	AtCoder ABC050: B. Contest with Drinks Easy
9057	AtCoder ABC050: A. Addition and Subtraction Easy
9056	AtCoder ABC049: B. Thin
9055	AtCoder ABC049: A. UOIAUAI
9054	AtCoder ABC048: B. Between a and b ...
9053	AtCoder ABC048: A. AtCoder *** Contest
9052	AtCoder ABC047: B. Snuke's Coloring 2 (ABC Edit)

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

9101

AtCoder ABC067: A. Sharing Cookies

9100

AtCoder ABC066: B. ss

9099

AtCoder ABC066: A. ringring

9098

AtCoder ABC065: B. Trained?

9097

AtCoder ABC065: A. Expired?

9096