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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)
4100 Codeforces 959C: Mahmoud and Ehab and the wrong algorithm
4099 Codeforces 959B: Mahmoud and Ehab and the message
4098 Codeforces 959A: Mahmoud and Ehab and the even-odd game
4097 Codeforces 958F3: Lightsabers (hard)
4096 Codeforces 958F2: Lightsabers (medium)
4095 Codeforces 958F1: Lightsabers (easy)
4094 Codeforces 958E3: Guard Duty (hard)
4093 Codeforces 958E2: Guard Duty (medium)
4092 Codeforces 958E1: Guard Duty (easy)
4091 Codeforces 958D2: Hyperspace Jump (hard)
4090 Codeforces 958D1: Hyperspace Jump (easy)
4089 Codeforces 958C3: Encryption (hard)
4088 Codeforces 958C2: Encryption (medium)
4087 Codeforces 958C1: Encryption (easy)
4086 Codeforces 958B2: Maximum Control (medium)
4085 Codeforces 958B1: Maximum Control (easy)
4084 Codeforces 958A3: Death Stars (hard)
4083 Codeforces 958A2: Death Stars (medium)
4082 Codeforces 958A1: Death Stars (easy)
4081 Codeforces 957A: Tritonic Iridescence
4080 Codeforces 955F: Heaps
4079 Codeforces 955E: Icicles
4078 Codeforces 955D: Scissors
4077 Codeforces 955C: Sad powers
4076 Codeforces 955B: Not simply beatiful strings
4075 Codeforces 955A: Feed the cat
4074 Codeforces 954I: Yet Another String Matching Problem
4073 Codeforces 954H: Path Counting
4072 Codeforces 954G: Castle Defense
4071 Codeforces 954F: Runner's Problem
4070 Codeforces 954E: Water Taps
4069 Codeforces 954D: Fight Against Traffic
4068 Codeforces 954C: Matrix Walk
4067 Codeforces 954B: String Typing
4066 Codeforces 954A: Diagonal Walking
4065 Codeforces 952G: Puzzling Language
4064 Codeforces 952F: 2 + 2 != 4
4063 Codeforces 952E: Cheese Board
4062 Codeforces 952D: I'm Feeling Lucky!
4061 Codeforces 952C: Ravioli Sort
4060 Codeforces 952B: A Map of the Cat
4059 Codeforces 952A: Quirky Quantifiers
4058 Codeforces 950B: Intercepted Message
4057 Codeforces 950A: Left-handers, Right-handers and Ambidexters
4056 Codeforces 949F: Astronomy
4055 Codeforces 949E: Binary Cards
4054 Codeforces 949D: Curfew
4053 Codeforces 949C: Data Center Maintenance
4052 Codeforces 949B: A Leapfrog in the Array
4051 Codeforces 949A: Zebras
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