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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)
1950 Codeforces 451C: Predict Outcome of the Game
1949 Codeforces 451B: Sort the Array
1948 Codeforces 451A: Game With Sticks
1947 Codeforces 450B: Jzzhu and Sequences
1946 Codeforces 450A: Jzzhu and Children
1945 Codeforces 449E: Jzzhu and Squares
1944 Codeforces 449D: Jzzhu and Numbers
1943 Codeforces 449C: Jzzhu and Apples
1942 Codeforces 449B: Jzzhu and Cities
1941 Codeforces 449A: Jzzhu and Chocolate
1940 Codeforces 448E: Divisors
1939 Codeforces 448D: Multiplication Table
1938 Codeforces 448C: Painting Fence
1937 Codeforces 448B: Suffix Structures
1936 Codeforces 448A: Rewards
1935 Codeforces 447B: DZY Loves Strings
1934 Codeforces 447A: DZY Loves Hash
1933 Codeforces 446E: DZY Loves Bridges
1932 Codeforces 446D: DZY Loves Games
1931 Codeforces 446C: DZY Loves Fibonacci Numbers
1930 Codeforces 446B: DZY Loves Modification
1929 Codeforces 446A: DZY Loves Sequences
1928 Codeforces 445B: DZY Loves Chemistry
1927 Codeforces 445A: DZY Loves Chessboard
1926 Codeforces 444E: DZY Loves Planting
1925 Codeforces 444D: DZY Loves Strings
1924 Codeforces 444C: DZY Loves Colors
1923 Codeforces 444B: DZY Loves FFT
1922 Codeforces 444A: DZY Loves Physics
1921 Codeforces 443B: Kolya and Tandem Repeat
1920 Codeforces 443A: Anton and Letters
1919 Codeforces 442E: Gena and Second Distance
1918 Codeforces 442D: Adam and Tree
1917 Codeforces 442C: Artem and Array
1916 Codeforces 442B: Andrey and Problem
1915 Codeforces 442A: Borya and Hanabi
1914 Codeforces 441E: Valera and Number
1913 Codeforces 441D: Valera and Swaps
1912 Codeforces 441C: Valera and Tubes
1911 Codeforces 441B: Valera and Fruits
1910 Codeforces 441A: Valera and Antique Items
1909 Codeforces 440D: Berland Federalization
1908 Codeforces 440C: One-Based Arithmetic
1907 Codeforces 440B: Balancer
1906 Codeforces 440A: Forgotten Episode
1905 Codeforces 439E: Devu and Birthday Celebration
1904 Codeforces 439D: Devu and his Brother
1903 Codeforces 439C: Devu and Partitioning of the Array
1902 Codeforces 439B: Devu, the Dumb Guy
1901 Codeforces 439A: Devu, the Singer and Churu, the Joker
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