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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)
3200 Codeforces 755C: PolandBall and Forest
3199 Codeforces 755B: PolandBall and Game
3198 Codeforces 755A: PolandBall and Hypothesis
3197 Codeforces 754E: Dasha and cyclic table
3196 Codeforces 754D: Fedor and coupons
3195 Codeforces 754C: Vladik and chat
3194 Codeforces 754B: Ilya and tic-tac-toe game
3193 Codeforces 754A: Lesha and array splitting
3192 Codeforces 753C: Interactive Bulls and Cows (Hard)
3191 Codeforces 753B: Interactive Bulls and Cows (Easy)
3190 Codeforces 753A: Santa Claus and Candies
3189 Codeforces 750H: New Year and Snowy Grid
3188 Codeforces 750G: New Year and Binary Tree Paths
3187 Codeforces 750F: New Year and Finding Roots
3186 Codeforces 750E: New Year and Old Subsequence
3185 Codeforces 750D: New Year and Fireworks
3184 Codeforces 750C: New Year and Rating
3183 Codeforces 750B: New Year and North Pole
3182 Codeforces 750A: New Year and Hurry
3181 Codeforces 749E: Inversions After Shuffle
3180 Codeforces 749D: Leaving Auction
3179 Codeforces 749C: Voting
3178 Codeforces 749B: Parallelogram is Back
3177 Codeforces 749A: Bachgold Problem
3176 Codeforces 748F: Santa Clauses and a Soccer Championship
3175 Codeforces 748E: Santa Claus and Tangerines
3174 Codeforces 748D: Santa Claus and a Palindrome
3173 Codeforces 748C: Santa Claus and Robot
3172 Codeforces 748B: Santa Claus and Keyboard Check
3171 Codeforces 748A: Santa Claus and a Place in a Class
3170 Codeforces 747F: Igor and Interesting Numbers
3169 Codeforces 747E: Comments
3168 Codeforces 747D: Winter Is Coming
3167 Codeforces 747C: Servers
3166 Codeforces 747B: Mammoth's Genome Decoding
3165 Codeforces 747A: Display Size
3164 Codeforces 746G: New Roads
3163 Codeforces 746F: Music in Car
3162 Codeforces 746E: Numbers Exchange
3161 Codeforces 746D: Green and Black Tea
3160 Codeforces 746C: Tram
3159 Codeforces 746B: Decoding
3158 Codeforces 746A: Compote
3157 Codeforces 745B: Hongcow Solves A Puzzle
3156 Codeforces 745A: Hongcow Learns the Cyclic Shift
3155 Codeforces 744E: Hongcow Masters the Cyclic Shift
3154 Codeforces 744D: Hongcow Draws a Circle
3153 Codeforces 744C: Hongcow Buys a Deck of Cards
3152 Codeforces 744B: Hongcow's Game
3151 Codeforces 744A: Hongcow Builds A Nation
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