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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)
1300 Codeforces 287B: Pipeline
1299 Codeforces 287A: IQ Test
1298 Codeforces 286E: Ladies' Shop
1297 Codeforces 286D: Tourists
1296 Codeforces 286C: Main Sequence
1295 Codeforces 286B: Shifting
1294 Codeforces 286A: Lucky Permutation
1293 Codeforces 285E: Positions in Permutations
1292 Codeforces 285D: Permutation Sum
1291 Codeforces 285C: Building Permutation
1290 Codeforces 285B: Find Marble
1289 Codeforces 285A: Slightly Decreasing Permutations
1288 Codeforces 284B: Cows and Poker Game
1287 Codeforces 284A: Cows and Primitive Roots
1286 Codeforces 283E: Cow Tennis Tournament
1285 Codeforces 283D: Cows and Cool Sequences
1284 Codeforces 283C: Coin Troubles
1283 Codeforces 283B: Cow Program
1282 Codeforces 283A: Cows and Sequence
1281 Codeforces 282E: Sausage Maximization
1280 Codeforces 282D: Yet Another Number Game
1279 Codeforces 282C: XOR and OR
1278 Codeforces 282B: Painting Eggs
1277 Codeforces 282A: Bit++
1276 Codeforces 281B: Nearest Fraction
1275 Codeforces 281A: Word Capitalization
1274 Codeforces 280E: Sequence Transformation
1273 Codeforces 280D: k-Maximum Subsequence Sum
1272 Codeforces 280C: Game on Tree
1271 Codeforces 280B: Maximum Xor Secondary
1270 Codeforces 280A: Rectangle Puzzle
1269 Codeforces 279E: Beautiful Decomposition
1268 Codeforces 279D: The Minimum Number of Variables
1267 Codeforces 279C: Ladder
1266 Codeforces 279B: Books
1265 Codeforces 279A: Point on Spiral
1264 Codeforces 278B: New Problem
1263 Codeforces 278A: Circle Line
1262 Codeforces 277E: Binary Tree on Plane
1261 Codeforces 277D: Google Code Jam
1260 Codeforces 277C: Game
1259 Codeforces 277B: Set of Points
1258 Codeforces 277A: Learning Languages
1257 Codeforces 276E: Little Girl and Problem on Trees
1256 Codeforces 276D: Little Girl and Maximum XOR
1255 Codeforces 276C: Little Girl and Maximum Sum
1254 Codeforces 276B: Little Girl and Game
1253 Codeforces 276A: Lunch Rush
1252 Codeforces 275B: Convex Shape
1251 Codeforces 275A: Lights Out
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