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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)
6450 Codeforces 1428A: Box is Pull
6449 Codeforces 1427H: Prison Break
6448 Codeforces 1427G: One Billion Shades of Grey
6447 Codeforces 1427F: Boring Card Game
6446 Codeforces 1427E: Xum
6445 Codeforces 1427D: Unshuffling a Deck
6444 Codeforces 1427C: The Hard Work of Paparazzi
6443 Codeforces 1427B: Chess Cheater
6442 Codeforces 1427A: Avoiding Zero
6441 Codeforces 1426F: Number of Subsequences
6440 Codeforces 1426E: Rock, Paper, Scissors
6439 Codeforces 1426D: Non-zero Segments
6438 Codeforces 1426C: Increase and Copy
6437 Codeforces 1426B: Symmetric Matrix
6436 Codeforces 1426A: Floor Number
6435 Codeforces 1425I: Impressive Harvesting of The Orchard
6434 Codeforces 1425H: Huge Boxes of Animal Toys
6433 Codeforces 1425F: Flamingoes of Mystery
6432 Codeforces 1425E: Excitation of Atoms
6431 Codeforces 1425D: Danger of Mad Snakes
6430 Codeforces 1425C: Captain of Knights
6429 Codeforces 1425B: Blue and Red of Our Faculty!
6428 Codeforces 1425A: Arena of Greed
6427 Codeforces 1424M: Ancient Language
6426 Codeforces 1424G: Years
6425 Codeforces 1423N: BubbleSquare Tokens
6424 Codeforces 1423M: Milutin's Plums
6423 Codeforces 1423L: Light switches
6422 Codeforces 1423K: Lonely Numbers
6421 Codeforces 1423J: Bubble Cup hypothesis
6420 Codeforces 1423I: Lookup Tables
6419 Codeforces 1423H: Virus
6418 Codeforces 1423G: Growing flowers
6417 Codeforces 1423F: Coins
6416 Codeforces 1423E: 5G Antenna Towers
6415 Codeforces 1423D: Does anyone else hate the wind?
6414 Codeforces 1423C: DuĊĦan's Railway
6413 Codeforces 1423B: Valuable Paper
6412 Codeforces 1423A: Wakanda Forever
6411 Codeforces 1422F: Boring Queries
6410 Codeforces 1422E: Minlexes
6409 Codeforces 1422D: Returning Home
6408 Codeforces 1422C: Bargain
6407 Codeforces 1422B: Nice Matrix
6406 Codeforces 1422A: Fence
6405 Codeforces 1421E: Swedish Heroes
6404 Codeforces 1421D: Hexagons
6403 Codeforces 1421C: Palindromifier
6402 Codeforces 1421B: Putting Bricks in the Wall
6401 Codeforces 1421A: XORwice
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