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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)
7550 Codeforces 1638B: Odd Swap Sort
7549 Codeforces 1638A: Reverse
7548 Codeforces 1637H: Minimize Inversions Number
7547 Codeforces 1637G: Birthday
7546 Codeforces 1637F: Towers
7545 Codeforces 1637E: Best Pair
7544 Codeforces 1637D: Yet Another Minimization Problem
7543 Codeforces 1637C: Andrew and Stones
7542 Codeforces 1637B: MEX and Array
7541 Codeforces 1637A: Sorting Parts
7540 Codeforces 1635F: Closest Pair
7539 Codeforces 1635E: Cars
7538 Codeforces 1635D: Infinite Set
7537 Codeforces 1635C: Differential Sorting
7536 Codeforces 1635B: Avoid Local Maximums
7535 Codeforces 1635A: Min Or Sum
7534 Codeforces 1634F: Fibonacci Additions
7533 Codeforces 1634E: Fair Share
7532 Codeforces 1634D: Finding Zero
7531 Codeforces 1634C: OKEA
7530 Codeforces 1634B: Fortune Telling
7529 Codeforces 1634A: Reverse and Concatenate
7528 Codeforces 1633F: Perfect Matching
7527 Codeforces 1633E: Spanning Tree Queries
7526 Codeforces 1633D: Make Them Equal
7525 Codeforces 1633C: Kill the Monster
7524 Codeforces 1633B: Minority
7523 Codeforces 1633A: Div. 7
7522 Codeforces 1632E2: Distance Tree (hard version)
7521 Codeforces 1632E1: Distance Tree (easy version)
7520 Codeforces 1632D: New Year Concert
7519 Codeforces 1632C: Strange Test
7518 Codeforces 1632B: Roof Construction
7517 Codeforces 1632A: ABC
7516 Codeforces 1631B: Fun with Even Subarrays
7515 Codeforces 1631A: Min Max Swap
7514 Codeforces 1630F: Making It Bipartite
7513 Codeforces 1630E: Expected Components
7512 Codeforces 1630D: Flipping Range
7511 Codeforces 1630C: Paint the Middle
7510 Codeforces 1630B: Range and Partition
7509 Codeforces 1630A: And Matching
7508 Codeforces 1629B: GCD Arrays
7507 Codeforces 1629A: Download More RAM
7506 Codeforces 1628F: Spaceship Crisis Management
7505 Codeforces 1628E: Groceries in Meteor Town
7504 Codeforces 1628D2: Game on Sum (Hard Version)
7503 Codeforces 1628D1: Game on Sum (Easy Version)
7502 Codeforces 1628C: Grid Xor
7501 Codeforces 1628B: Peculiar Movie Preferences
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