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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)
450 Codeforces 87B: Vasya and Types
449 Codeforces 87A: Trains
448 Codeforces 86E: Long sequence
447 Codeforces 86D: Powerful array
446 Codeforces 86C: Genetic engineering
445 Codeforces 86B: Tetris revisited
444 Codeforces 86A: Reflection
443 Codeforces 85E: Guard Towers
442 Codeforces 85D: Sum of Medians
441 Codeforces 85C: Petya and Tree
440 Codeforces 85B: Embassy Queue
439 Codeforces 85A: Domino
438 Codeforces 84C: Biathlon
437 Codeforces 84A: Toy Army
436 Codeforces 83E: Two Subsequences
435 Codeforces 83D: Numbers
434 Codeforces 83C: Track
433 Codeforces 83B: Doctor
432 Codeforces 83A: Magical Array
431 Codeforces 82E: Corridor
430 Codeforces 82D: Two out of Three
429 Codeforces 82C: General Mobilization
428 Codeforces 82B: Sets
427 Codeforces 82A: Double Cola
426 Codeforces 81E: Pairs
425 Codeforces 81D: Polycarp's Picture Gallery
424 Codeforces 81C: Average Score
423 Codeforces 81B: Sequence Formatting
422 Codeforces 81A: Plug-in
421 Codeforces 80B: Depression
420 Codeforces 80A: Panoramix's Prediction
419 Codeforces 79E: Security System
418 Codeforces 79D: Password
417 Codeforces 79C: Beaver
416 Codeforces 79B: Colorful Field
415 Codeforces 79A: Bus Game
414 Codeforces 78E: Evacuation
413 Codeforces 78D: Archer's Shot
412 Codeforces 78C: Beaver Game
411 Codeforces 78B: Easter Eggs
410 Codeforces 78A: Haiku
409 Codeforces 77E: Martian Food
408 Codeforces 77D: Domino Carpet
407 Codeforces 77C: Beavermuncher-0xFF
406 Codeforces 77B: Falling Anvils
405 Codeforces 77A: Heroes
404 Codeforces 76F: Tourist
403 Codeforces 76E: Points
402 Codeforces 76D: Plus and xor
401 Codeforces 76C: Mutation
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