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)
9201	AtCoder ABC103: C. Modulo Summation
9200	AtCoder ABC103: B. String Rotation
9199	AtCoder ABC103: A. Task Scheduling Problem
9198	AtCoder ABC102: B. Maximum Difference
9197	AtCoder ABC102: A. Multiple of 2 and N
9196	AtCoder ABC101: B. Digit Sums
9195	AtCoder ABC101: A. Eating Symbols Easy
9194	AtCoder ABC100: D. Patisserie ABC
9193	AtCoder ABC100: C. *3 or /2
9192	AtCoder ABC100: B. Ringo's Favorite Numbers
9191	AtCoder ABC100: A. Happy Birthday!
9190	AtCoder ABC099: D. Good Grid
9189	AtCoder ABC099: C. Strange Bank
9188	AtCoder ABC099: B. Stone Monument
9187	AtCoder ABC099: A. ABD
9186	AtCoder ABC098: B. Cut and Count
9185	AtCoder ABC098: A. Add Sub Mul
9184	AtCoder ABC097: B. Exponential
9183	AtCoder ABC097: A. Colorful Transceivers
9182	AtCoder ABC096: D. Five, Five Everywhere
9181	AtCoder ABC096: C. Grid Repainting 2
9180	AtCoder ABC096: B. Maximum Sum
9179	AtCoder ABC096: A. Day of Takahashi
9178	AtCoder ABC095: B. Bitter Alchemy
9177	AtCoder ABC095: A. Something on It
9176	AtCoder ABC094: B. Toll Gates
9175	AtCoder ABC094: A. Cats and Dogs
9174	AtCoder ABC093: B. Small and Large Integers
9173	AtCoder ABC093: A. abc of ABC
9172	AtCoder ABC092: B. Chocolate
9171	AtCoder ABC092: A. Traveling Budget
9170	AtCoder ABC091: B. Two Colors Card Game
9169	AtCoder ABC091: A. Two Coins
9168	AtCoder ABC090: B. Palindromic Numbers
9167	AtCoder ABC090: A. Diagonal String
9166	AtCoder ABC089: D. Practical Skill Test
9165	AtCoder ABC089: C. March
9164	AtCoder ABC089: B. Hina Arare
9163	AtCoder ABC089: A. Grouping 2
9162	AtCoder ABC088: D. Grid Repainting
9161	AtCoder ABC088: C. Takahashi's Information
9160	AtCoder ABC088: B. Card Game for Two
9159	AtCoder ABC088: A. Infinite Coins
9158	AtCoder ABC087: B. Coins
9157	AtCoder ABC087: A. Buying Sweets
9156	AtCoder ABC086: B. 1 21
9155	AtCoder ABC086: A. Product
9154	AtCoder ABC085: D. Katana Thrower
9153	AtCoder ABC085: C. Otoshidama
9152	AtCoder ABC085: B. Kagami Mochi

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

9201

AtCoder ABC103: C. Modulo Summation

9200

AtCoder ABC103: B. String Rotation

9199

AtCoder ABC103: A. Task Scheduling Problem

9198

AtCoder ABC102: B. Maximum Difference

9197

AtCoder ABC102: A. Multiple of 2 and N

9196