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Over 20,000 problems available: AMC 8/10/12 and AIME problems from 2010-2024; USAJMO/USAMO problems from 2002-2024; USACO problems from 2014 to 2024 (all divisions); all Codeforces, AtCoder and DMOJ problems. If you leave the search field blank, it returns all problems with the specified type.

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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)
5200 Codeforces 1185E: Polycarp and Snakes
5199 Codeforces 1185D: Extra Element
5198 Codeforces 1185C2: Exam in BerSU (hard version)
5197 Codeforces 1185C1: Exam in BerSU (easy version)
5196 Codeforces 1185B: Email from Polycarp
5195 Codeforces 1185A: Ropewalkers
5194 Codeforces 1184E3: Daleks' Invasion (hard)
5193 Codeforces 1184E2: Daleks' Invasion (medium)
5192 Codeforces 1184E1: Daleks' Invasion (easy)
5191 Codeforces 1184D2: Parallel Universes (Hard)
5190 Codeforces 1184D1: Parallel Universes (Easy)
5189 Codeforces 1184C3: Heidi and the Turing Test (Hard)
5188 Codeforces 1184C2: Heidi and the Turing Test (Medium)
5187 Codeforces 1184C1: Heidi and the Turing Test (Easy)
5186 Codeforces 1184B3: The Doctor Meets Vader (Hard)
5185 Codeforces 1184B2: The Doctor Meets Vader (Medium)
5184 Codeforces 1184B1: The Doctor Meets Vader (Easy)
5183 Codeforces 1184A3: Heidi Learns Hashing (Hard)
5182 Codeforces 1184A2: Heidi Learns Hashing (Medium)
5181 Codeforces 1184A1: Heidi Learns Hashing (Easy)
5180 Codeforces 1183H: Subsequences (hard version)
5179 Codeforces 1183G: Candy Box (hard version)
5178 Codeforces 1183F: Topforces Strikes Back
5177 Codeforces 1183E: Subsequences (easy version)
5176 Codeforces 1183D: Candy Box (easy version)
5175 Codeforces 1183C: Computer Game
5174 Codeforces 1183B: Equalize Prices
5173 Codeforces 1183A: Nearest Interesting Number
5172 Codeforces 1182F: Maximum Sine
5171 Codeforces 1182E: Product Oriented Recurrence
5170 Codeforces 1182D: Complete Mirror
5169 Codeforces 1182C: Beautiful Lyrics
5168 Codeforces 1182B: Plus from Picture
5167 Codeforces 1182A: Filling Shapes
5166 Codeforces 1181E2: A Story of One Country (Hard)
5165 Codeforces 1181E1: A Story of One Country (Easy)
5164 Codeforces 1181D: Irrigation
5163 Codeforces 1181C: Flag
5162 Codeforces 1181B: Split a Number
5161 Codeforces 1181A: Chunga-Changa
5160 Codeforces 1180B: Nick and Array
5159 Codeforces 1180A: Alex and a Rhombus
5158 Codeforces 1179E: Alesya and Discrete Math
5157 Codeforces 1179D: Fedor Runs for President
5156 Codeforces 1179C: Serge and Dining Room
5155 Codeforces 1179B: Tolik and His Uncle
5154 Codeforces 1179A: Valeriy and Deque
5153 Codeforces 1178H: Stock Exchange
5152 Codeforces 1178G: The Awesomest Vertex
5151 Codeforces 1178F2: Long Colorful Strip
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