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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)
7200 Codeforces 1573B: Swaps
7199 Codeforces 1573A: Countdown
7198 Codeforces 1572F: Stations
7197 Codeforces 1572E: Polygon
7196 Codeforces 1572D: Bridge Club
7195 Codeforces 1572C: Paint
7194 Codeforces 1572B: Xor of 3
7193 Codeforces 1572A: Book
7192 Codeforces 1571J: Two Railroads
7191 Codeforces 1571I: Physical Examination
7190 Codeforces 1571H: Laser Beams
7189 Codeforces 1571G: A Battle Against a Dragon
7188 Codeforces 1571F: Kotlinforces
7187 Codeforces 1571E: Fix the String
7186 Codeforces 1571D: Sweepstake
7185 Codeforces 1571C: Rhyme
7184 Codeforces 1571B: Epic Novel
7183 Codeforces 1571A: Sequence of Comparisons
7182 Codeforces 1569F: Palindromic Hamiltonian Path
7181 Codeforces 1569E: Playoff Restoration
7180 Codeforces 1569D: Inconvenient Pairs
7179 Codeforces 1569C: Jury Meeting
7178 Codeforces 1569B: Chess Tournament
7177 Codeforces 1569A: Balanced Substring
7176 Codeforces 1567F: One-Four Overload
7175 Codeforces 1567E: Non-Decreasing Dilemma
7174 Codeforces 1567D: Expression Evaluation Error
7173 Codeforces 1567C: Carrying Conundrum
7172 Codeforces 1567B: MEXor Mixup
7171 Codeforces 1567A: Domino Disaster
7170 Codeforces 1566H: Xor-quiz
7169 Codeforces 1566G: Four Vertices
7168 Codeforces 1566F: Points Movement
7167 Codeforces 1566E: Buds Re-hanging
7166 Codeforces 1566D2: Seating Arrangements (hard version)
7165 Codeforces 1566D1: Seating Arrangements (easy version)
7164 Codeforces 1566C: MAX-MEX Cut
7163 Codeforces 1566B: MIN-MEX Cut
7162 Codeforces 1566A: Median Maximization
7161 Codeforces 1562F: Tubular Bells
7160 Codeforces 1562E: Rescue Niwen!
7159 Codeforces 1562D2: Two Hundred Twenty One (hard version)
7158 Codeforces 1562D1: Two Hundred Twenty One (easy version)
7157 Codeforces 1562C: Rings
7156 Codeforces 1562B: Scenes From a Memory
7155 Codeforces 1562A: The Miracle and the Sleeper
7154 Codeforces 1561D1: Up the Strip (simplified version)
7153 Codeforces 1561C: Deep Down Below
7152 Codeforces 1561A: Simply Strange Sort
7151 Codeforces 1560F2: Nearest Beautiful Number (hard version)
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