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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)
7250 Codeforces 1582A: Luntik and Concerts
7249 Codeforces 1581B: Diameter of Graph
7248 Codeforces 1581A: CQXYM Count Permutations
7247 Codeforces 1580F: Problems for Codeforces
7246 Codeforces 1580E: Railway Construction
7245 Codeforces 1580D: Subsequence
7244 Codeforces 1580C: Train Maintenance
7243 Codeforces 1580B: Mathematics Curriculum
7242 Codeforces 1580A: Portal
7241 Codeforces 1579G: Minimal Coverage
7240 Codeforces 1579F: Array Stabilization (AND version)
7239 Codeforces 1579E2: Array Optimization by Deque
7238 Codeforces 1579E1: Permutation Minimization by Deque
7237 Codeforces 1579D: Productive Meeting
7236 Codeforces 1579C: Ticks
7235 Codeforces 1579B: Shifting Sort
7234 Codeforces 1579A: Casimir's String Solitaire
7233 Codeforces 1578M: The Mind
7232 Codeforces 1578L: Labyrinth
7231 Codeforces 1578K: Kingdom of Islands
7230 Codeforces 1578J: Just Kingdom
7229 Codeforces 1578I: Interactive Rays
7228 Codeforces 1578H: Higher Order Functions
7227 Codeforces 1578G: Game of Chance
7226 Codeforces 1578F: Framing Pictures
7225 Codeforces 1578E: Easy Scheduling
7224 Codeforces 1578D: Dragon Curve
7223 Codeforces 1578C: Cactus Lady and her Cing
7222 Codeforces 1578B: Building Forest Trails
7221 Codeforces 1578A: Anti-Tetris
7220 Codeforces 1576A: Communication Routing Challenge
7219 Codeforces 1575M: Managing Telephone Poles
7218 Codeforces 1575L: Longest Array Deconstruction
7217 Codeforces 1575K: Knitting Batik
7216 Codeforces 1575J: Jeopardy of Dropped Balls
7215 Codeforces 1575I: Illusions of the Desert
7214 Codeforces 1575H: Holiday Wall Ornaments
7213 Codeforces 1575G: GCD Festival
7212 Codeforces 1575F: Finding Expected Value
7211 Codeforces 1575E: Eye-Pleasing City Park Tour
7210 Codeforces 1575D: Divisible by Twenty-Five
7209 Codeforces 1575C: Cyclic Sum
7208 Codeforces 1575B: Building an Amusement Park
7207 Codeforces 1575A: Another Sorting Problem
7206 Codeforces 1574F: Occurrences
7205 Codeforces 1574E: Coloring
7204 Codeforces 1574D: The Strongest Build
7203 Codeforces 1574C: Slay the Dragon
7202 Codeforces 1574B: Combinatorics Homework
7201 Codeforces 1574A: Regular Bracket Sequences
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