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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)
1100 Codeforces 237E: Build String
1099 Codeforces 237D: T-decomposition
1098 Codeforces 237C: Primes on Interval
1097 Codeforces 237B: Young Table
1096 Codeforces 237A: Free Cash
1095 Codeforces 236B: Easy Number Challenge
1094 Codeforces 236A: Boy or Girl
1093 Codeforces 235E: Number Challenge
1092 Codeforces 235D: Graph Game
1091 Codeforces 235C: Cyclical Quest
1090 Codeforces 235B: Let's Play Osu!
1089 Codeforces 235A: LCM Challenge
1088 Codeforces 234H: Merging Two Decks
1087 Codeforces 234G: Practice
1086 Codeforces 234F: Fence
1085 Codeforces 234E: Champions' League
1084 Codeforces 234D: Cinema
1083 Codeforces 234C: Weather
1082 Codeforces 234B: Reading
1081 Codeforces 234A: Lefthanders and Righthanders
1080 Codeforces 233B: Non-square Equation
1079 Codeforces 233A: Perfect Permutation
1078 Codeforces 232E: Quick Tortoise
1077 Codeforces 232D: Fence
1076 Codeforces 232C: Doe Graphs
1075 Codeforces 232B: Table
1074 Codeforces 232A: Cycles
1073 Codeforces 231E: Cactus
1072 Codeforces 231D: Magic Box
1071 Codeforces 231C: To Add or Not to Add
1070 Codeforces 231B: Magic, Wizardry and Wonders
1069 Codeforces 231A: Team
1068 Codeforces 230B: T-primes
1067 Codeforces 230A: Dragons
1066 Codeforces 229E: Gifts
1065 Codeforces 229D: Towers
1064 Codeforces 229C: Triangles
1063 Codeforces 229B: Planets
1062 Codeforces 229A: Shifts
1061 Codeforces 228E: The Road to Berland is Paved With Good Intentions
1060 Codeforces 228D: Zigzag
1059 Codeforces 228C: Fractal Detector
1058 Codeforces 228B: Two Tables
1057 Codeforces 228A: Is your horseshoe on the other hoof?
1056 Codeforces 227B: Effective Approach
1055 Codeforces 227A: Where do I Turn?
1054 Codeforces 226E: Noble Knight's Path
1053 Codeforces 226D: The table
1052 Codeforces 226C: Anniversary
1051 Codeforces 226B: Naughty Stone Piles
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