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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)
6100 Codeforces 1361C: Johnny and Megan's Necklace
6099 Codeforces 1361B: Johnny and Grandmaster
6098 Codeforces 1361A: Johnny and Contribution
6097 Codeforces 1360H: Binary Median
6096 Codeforces 1360G: A/B Matrix
6095 Codeforces 1360F: Spy-string
6094 Codeforces 1360E: Polygon
6093 Codeforces 1360D: Buying Shovels
6092 Codeforces 1360C: Similar Pairs
6091 Codeforces 1360B: Honest Coach
6090 Codeforces 1360A: Minimal Square
6089 Codeforces 1359F: RC Kaboom Show
6088 Codeforces 1359E: Modular Stability
6087 Codeforces 1359D: Yet Another Yet Another Task
6086 Codeforces 1359C: Mixing Water
6085 Codeforces 1359B: New Theatre Square
6084 Codeforces 1359A: Berland Poker
6083 Codeforces 1358F: Tasty Cookie
6082 Codeforces 1358E: Are You Fired?
6081 Codeforces 1358D: The Best Vacation
6080 Codeforces 1358C: Celex Update
6079 Codeforces 1358B: Maria Breaks the Self-isolation
6078 Codeforces 1358A: Park Lighting
6077 Codeforces 1357E2: Root of quantum Fourier transform
6076 Codeforces 1357E1: Power of quantum Fourier transform
6075 Codeforces 1357D5: Quantum Classification - Dataset 7
6074 Codeforces 1357D4: Quantum Classification - Dataset 6
6073 Codeforces 1357D3: Quantum Classification - Dataset 5
6072 Codeforces 1357D2: Quantum Classification - Dataset 4
6071 Codeforces 1357D1: Quantum Classification - Dataset 3
6070 Codeforces 1357C2: Prepare superposition of basis states with the same parity
6069 Codeforces 1357C1: Prepare superposition of basis states with 0s
6068 Codeforces 1357B2: "Is the number divisible by 3?" oracle
6067 Codeforces 1357B1: "Is the bit string balanced?" oracle
6066 Codeforces 1357A7: Distinguish Y, XZ, -Y and -XZ
6065 Codeforces 1357A6: Distinguish four Pauli gates
6064 Codeforces 1357A5: Distinguish Rz(θ) from Ry(θ)
6063 Codeforces 1357A4: Distinguish Rz from R1
6062 Codeforces 1357A3: Distinguish H from X
6061 Codeforces 1357A2: Distinguish I, CNOTs and SWAP
6060 Codeforces 1357A1: Figure out direction of CNOT
6059 Codeforces 1356D2: Quantum Classification - 2
6058 Codeforces 1356D1: Quantum Classification - 1
6057 Codeforces 1356C: Prepare state |01⟩ + |10⟩ + |11⟩
6056 Codeforces 1356B2: Decrement
6055 Codeforces 1356B1: Increment
6054 Codeforces 1356A5: Distinguish Z from -Z
6053 Codeforces 1356A4: Distinguish I ⊗ X from CNOT
6052 Codeforces 1356A3: Distinguish Z from S
6051 Codeforces 1356A2: Distinguish I from Z
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