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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)
2350 Codeforces 550C: Divisibility by Eight
2349 Codeforces 550B: Preparing Olympiad
2348 Codeforces 550A: Two Substrings
2347 Codeforces 549H: Degenerate Matrix
2346 Codeforces 549G: Happy Line
2345 Codeforces 549F: Yura and Developers
2344 Codeforces 549E: Sasha Circle
2343 Codeforces 549D: Haar Features
2342 Codeforces 549C: The Game Of Parity
2341 Codeforces 549B: Looksery Party
2340 Codeforces 549A: Face Detection
2339 Codeforces 548B: Mike and Fun
2338 Codeforces 548A: Mike and Fax
2337 Codeforces 547E: Mike and Friends
2336 Codeforces 547D: Mike and Fish
2335 Codeforces 547C: Mike and Foam
2334 Codeforces 547B: Mike and Feet
2333 Codeforces 547A: Mike and Frog
2332 Codeforces 546E: Soldier and Traveling
2331 Codeforces 546D: Soldier and Number Game
2330 Codeforces 546C: Soldier and Cards
2329 Codeforces 546B: Soldier and Badges
2328 Codeforces 546A: Soldier and Bananas
2327 Codeforces 545E: Paths and Trees
2326 Codeforces 545D: Queue
2325 Codeforces 545C: Woodcutters
2324 Codeforces 545B: Equidistant String
2323 Codeforces 545A: Toy Cars
2322 Codeforces 544B: Sea and Islands
2321 Codeforces 544A: Set of Strings
2320 Codeforces 543E: Listening to Music
2319 Codeforces 543D: Road Improvement
2318 Codeforces 543C: Remembering Strings
2317 Codeforces 543B: Destroying Roads
2316 Codeforces 543A: Writing Code
2315 Codeforces 542F: Quest
2314 Codeforces 542E: Playing on Graph
2313 Codeforces 542D: Superhero's Job
2312 Codeforces 542C: Idempotent functions
2311 Codeforces 542B: Duck Hunt
2310 Codeforces 542A: Place Your Ad Here
2309 Codeforces 540E: Infinite Inversions
2308 Codeforces 540D: Bad Luck Island
2307 Codeforces 540C: Ice Cave
2306 Codeforces 540B: School Marks
2305 Codeforces 540A: Combination Lock
2304 Codeforces 538H: Summer Dichotomy
2303 Codeforces 538G: Berserk Robot
2302 Codeforces 538F: A Heap of Heaps
2301 Codeforces 538E: Demiurges Play Again
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