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)
9401	AtCoder ABC145: C. Average Length
9400	AtCoder ABC145: B. Echo
9399	AtCoder ABC145: A. Circle
9398	AtCoder ABC144: F. Fork in the Road
9397	AtCoder ABC144: E. Gluttony
9396	AtCoder ABC144: D. Water Bottle
9395	AtCoder ABC144: C. Walk on Multiplication Table
9394	AtCoder ABC144: B. 81
9393	AtCoder ABC144: A. 9x9
9392	AtCoder ABC143: F. Distinct Numbers
9391	AtCoder ABC143: E. Travel by Car
9390	AtCoder ABC143: D. Triangles
9389	AtCoder ABC143: C. Slimes
9388	AtCoder ABC143: B. TAKOYAKI FESTIVAL 2019
9387	AtCoder ABC143: A. Curtain
9386	AtCoder ABC142: F. Pure
9385	AtCoder ABC142: E. Get Everything
9384	AtCoder ABC142: D. Disjoint Set of Common Divisors
9383	AtCoder ABC142: C. Go to School
9382	AtCoder ABC142: B. Roller Coaster
9381	AtCoder ABC142: A. Odds of Oddness
9380	AtCoder ABC141: F. Xor Sum 3
9379	AtCoder ABC141: E. Who Says a Pun?
9378	AtCoder ABC141: D. Powerful Discount Tickets
9377	AtCoder ABC141: C. Attack Survival
9376	AtCoder ABC141: B. Tap Dance
9375	AtCoder ABC141: A. Weather Prediction
9374	AtCoder ABC140: F. Many Slimes
9373	AtCoder ABC140: E. Second Sum
9372	AtCoder ABC140: D. Face Produces Unhappiness
9371	AtCoder ABC140: C. Maximal Value
9370	AtCoder ABC140: B. Buffet
9369	AtCoder ABC140: A. Password
9368	AtCoder ABC139: F. Engines
9367	AtCoder ABC139: E. League
9366	AtCoder ABC139: D. ModSum
9365	AtCoder ABC139: C. Lower
9364	AtCoder ABC139: B. Power Socket
9363	AtCoder ABC139: A. Tenki
9362	AtCoder ABC138: F. Coincidence
9361	AtCoder ABC138: E. Strings of Impurity
9360	AtCoder ABC138: D. Ki
9359	AtCoder ABC138: C. Alchemist
9358	AtCoder ABC138: B. Resistors in Parallel
9357	AtCoder ABC138: A. Red or Not
9356	AtCoder ABC137: F. Polynomial Construction
9355	AtCoder ABC137: E. Coins Respawn
9354	AtCoder ABC137: D. Summer Vacation
9353	AtCoder ABC137: C. Green Bin
9352	AtCoder ABC137: B. One Clue

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

9401

AtCoder ABC145: C. Average Length

9400

AtCoder ABC145: B. Echo

9399

AtCoder ABC145: A. Circle

9398

AtCoder ABC144: F. Fork in the Road

9397

AtCoder ABC144: E. Gluttony

9396