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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)
1900 Codeforces 438E: The Child and Binary Tree
1899 Codeforces 438D: The Child and Sequence
1898 Codeforces 437E: The Child and Polygon
1897 Codeforces 437D: The Child and Zoo
1896 Codeforces 437C: The Child and Toy
1895 Codeforces 437B: The Child and Set
1894 Codeforces 437A: The Child and Homework
1893 Codeforces 436F: Banners
1892 Codeforces 436E: Cardboard Box
1891 Codeforces 436D: Pudding Monsters
1890 Codeforces 436C: Dungeons and Candies
1889 Codeforces 436B: Om Nom and Spiders
1888 Codeforces 436A: Feed with Candy
1887 Codeforces 435E: Special Graph
1886 Codeforces 435D: Special Grid
1885 Codeforces 435C: Cardiogram
1884 Codeforces 435B: Pasha Maximizes
1883 Codeforces 435A: Queue on Bus Stop
1882 Codeforces 434E: Furukawa Nagisa's Tree
1881 Codeforces 434D: Nanami's Power Plant
1880 Codeforces 433E: Tachibana Kanade's Tofu
1879 Codeforces 433D: Nanami's Digital Board
1878 Codeforces 433C: Ryouko's Memory Note
1877 Codeforces 433B: Kuriyama Mirai's Stones
1876 Codeforces 433A: Kitahara Haruki's Gift
1875 Codeforces 432E: Square Tiling
1874 Codeforces 432D: Prefixes and Suffixes
1873 Codeforces 432C: Prime Swaps
1872 Codeforces 432B: Football Kit
1871 Codeforces 432A: Choosing Teams
1870 Codeforces 431E: Chemistry Experiment
1869 Codeforces 431D: Random Task
1868 Codeforces 431C: k-Tree
1867 Codeforces 431B: Shower Line
1866 Codeforces 431A: Black Square
1865 Codeforces 430B: Balls Game
1864 Codeforces 430A: Points and Segments (easy)
1863 Codeforces 429E: Points and Segments
1862 Codeforces 429D: Tricky Function
1861 Codeforces 429C: Guess the Tree
1860 Codeforces 429B: Working out
1859 Codeforces 429A: Xor-tree
1858 Codeforces 427E: Police Patrol
1857 Codeforces 427D: Match & Catch
1856 Codeforces 427C: Checkposts
1855 Codeforces 427B: Prison Transfer
1854 Codeforces 427A: Police Recruits
1853 Codeforces 426B: Sereja and Mirroring
1852 Codeforces 426A: Sereja and Mugs
1851 Codeforces 425E: Sereja and Sets
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