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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)
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
3150 Codeforces 743E: Vladik and cards
3149 Codeforces 743D: Chloe and pleasant prizes
3148 Codeforces 743C: Vladik and fractions
3147 Codeforces 743B: Chloe and the sequence
3146 Codeforces 743A: Vladik and flights
3145 Codeforces 742B: Arpa’s obvious problem and Mehrdad’s terrible solution
3144 Codeforces 742A: Arpa’s hard exam and Mehrdad’s naive cheat
3143 Codeforces 741E: Arpa’s abnormal DNA and Mehrdad’s deep interest
3142 Codeforces 741D: Arpa’s letter-marked tree and Mehrdad’s Dokhtar-kosh paths
3141 Codeforces 741C: Arpa’s overnight party and Mehrdad’s silent entering
3140 Codeforces 741B: Arpa's weak amphitheater and Mehrdad's valuable Hoses
3139 Codeforces 741A: Arpa's loud Owf and Mehrdad's evil plan
3138 Codeforces 740B: Alyona and flowers
3137 Codeforces 740A: Alyona and copybooks
3136 Codeforces 739E: Gosha is hunting
3135 Codeforces 739D: Recover a functional graph
3134 Codeforces 739C: Alyona and towers
3133 Codeforces 739B: Alyona and a tree
3132 Codeforces 739A: Alyona and mex
3131 Codeforces 737F: Dirty plates
3130 Codeforces 737E: Tanya is 5!
3129 Codeforces 736E: Chess Championship
3128 Codeforces 736D: Permutations
3127 Codeforces 735E: Ostap and Tree
3126 Codeforces 735D: Taxes
3125 Codeforces 735C: Tennis Championship
3124 Codeforces 735B: Urbanization
3123 Codeforces 735A: Ostap and Grasshopper
3122 Codeforces 734F: Anton and School
3121 Codeforces 734E: Anton and Tree
3120 Codeforces 734D: Anton and Chess
3119 Codeforces 734C: Anton and Making Potions
3118 Codeforces 734B: Anton and Digits
3117 Codeforces 734A: Anton and Danik
3116 Codeforces 733F: Drivers Dissatisfaction
3115 Codeforces 733E: Sleep in Class
3114 Codeforces 733D: Kostya the Sculptor
3113 Codeforces 733C: Epidemic in Monstropolis
3112 Codeforces 733B: Parade
3111 Codeforces 733A: Grasshopper And the String
3110 Codeforces 732F: Tourist Reform
3109 Codeforces 732E: Sockets
3108 Codeforces 732D: Exams
3107 Codeforces 732C: Sanatorium
3106 Codeforces 732B: Cormen --- The Best Friend Of a Man
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