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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)
25205 Codeforces 1977A: Little Nikita
25204 Codeforces 1976F: Remove Bridges
25203 Codeforces 1976E: Splittable Permutations
25202 Codeforces 1976D: Invertible Bracket Sequences
25201 Codeforces 1976C: Job Interview
25200 Codeforces 1976B: Increase/Decrease/Copy
25199 Codeforces 1976A: Verify Password
25198 Codeforces 1975I: Mind Bloom
25197 Codeforces 1975H: 378QAQ and Core
25196 Codeforces 1975G: Zimpha Fan Club
25195 Codeforces 1975F: Set
25194 Codeforces 1975E: Chain Queries
25193 Codeforces 1975D: Paint the Tree
25192 Codeforces 1975C: Chamo and Mocha's Array
25191 Codeforces 1975B: 378QAQ and Mocha's Array
25190 Codeforces 1975A: Bazoka and Mocha's Array
25189 Codeforces 1974G: Money Buys Less Happiness Now
25188 Codeforces 1974F: Cutting Game
25187 Codeforces 1974E: Money Buys Happiness
25186 Codeforces 1974D: Ingenuity-2
25185 Codeforces 1974C: Beautiful Triple Pairs
25184 Codeforces 1974B: Symmetric Encoding
25183 Codeforces 1974A: Phone Desktop
25182 Codeforces 1973F: Maximum GCD Sum Queries
25181 Codeforces 1973E: Cat, Fox and Swaps
25180 Codeforces 1973D: Cat, Fox and Maximum Array Split
25179 Codeforces 1973C: Cat, Fox and Double Maximum
25178 Codeforces 1973B: Cat, Fox and the Lonely Array
25177 Codeforces 1973A: Chess For Three
25176 Codeforces 1972B: Coin Games
25175 Codeforces 1972A: Contest Proposal
25174 Codeforces 1971H: ±1
25173 Codeforces 1971G: XOUR
25172 Codeforces 1971F: Circle Perimeter
25171 Codeforces 1971E: Find the Car
25170 Codeforces 1971D: Binary Cut
25169 Codeforces 1971C: Clock and Strings
25168 Codeforces 1971B: Different String
25167 Codeforces 1971A: My First Sorting Problem
25166 Codeforces 1970G3: Min-Fund Prison (Hard)
25165 Codeforces 1970G2: Min-Fund Prison (Medium)
25164 Codeforces 1970G1: Min-Fund Prison (Easy)
25163 Codeforces 1970F3: Playing Quidditch (Hard)
25162 Codeforces 1970F2: Playing Quidditch (Medium)
25161 Codeforces 1970F1: Playing Quidditch (Easy)
25160 Codeforces 1970E3: Trails (Hard)
25159 Codeforces 1970E2: Trails (Medium)
25158 Codeforces 1970E1: Trails (Easy)
25157 Codeforces 1970D3: Arithmancy (Hard)
25156 Codeforces 1970D2: Arithmancy (Medium)
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