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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)
8550 Codeforces 1808C: Unlucky Numbers
8549 Codeforces 1808B: Playing in a Casino
8548 Codeforces 1808A: Lucky Numbers
8547 Codeforces 1807G2: Subsequence Addition (Hard Version)
8546 Codeforces 1807G1: Subsequence Addition (Easy Version)
8545 Codeforces 1807F: Bouncy Ball
8544 Codeforces 1807E: Interview
8543 Codeforces 1807D: Odd Queries
8542 Codeforces 1807C: Find and Replace
8541 Codeforces 1807B: Grab the Candies
8540 Codeforces 1807A: Plus or Minus
8539 Codeforces 1806F2: GCD Master (hard version)
8538 Codeforces 1806F1: GCD Master (easy version)
8537 Codeforces 1806E: Tree Master
8536 Codeforces 1806D: DSU Master
8535 Codeforces 1806C: Sequence Master
8534 Codeforces 1806B: Mex Master
8533 Codeforces 1806A: Walking Master
8532 Codeforces 1805F2: Survival of the Weakest (hard version)
8531 Codeforces 1805F1: Survival of the Weakest (easy version)
8530 Codeforces 1805E: There Should Be a Lot of Maximums
8529 Codeforces 1805D: A Wide, Wide Graph
8528 Codeforces 1805C: Place for a Selfie
8527 Codeforces 1805B: The String Has a Target
8526 Codeforces 1805A: We Need the Zero
8525 Codeforces 1804H: Code Lock
8524 Codeforces 1804G: Flow Control
8523 Codeforces 1804F: Approximate Diameter
8522 Codeforces 1804E: Routing
8521 Codeforces 1804D: Accommodation
8520 Codeforces 1804C: Pull Your Luck
8519 Codeforces 1804B: Vaccination
8518 Codeforces 1804A: Lame King
8517 Codeforces 1802B: Settlement of Guinea Pigs
8516 Codeforces 1802A: Likes
8515 Codeforces 1801G: A task for substrings
8514 Codeforces 1801F: Another n-dimensional chocolate bar
8513 Codeforces 1801E: Gasoline prices
8512 Codeforces 1801D: The way home
8511 Codeforces 1801C: Music Festival
8510 Codeforces 1801B: Buying gifts
8509 Codeforces 1801A: The Very Beautiful Blanket
8508 Codeforces 1800G: Symmetree
8507 Codeforces 1800F: Dasha and Nightmares
8506 Codeforces 1800E2: Unforgivable Curse (hard version)
8505 Codeforces 1800E1: Unforgivable Curse (easy version)
8504 Codeforces 1800D: Remove Two Letters
8503 Codeforces 1800C2: Powering the Hero (hard version)
8502 Codeforces 1800C1: Powering the Hero (easy version)
8501 Codeforces 1800B: Count the Number of Pairs
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