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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
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ID Problem Name (click to add insights/hints, view summary of insights/hints and similar problems)
6250 Codeforces 1389D: Segment Intersections
6249 Codeforces 1389C: Good String
6248 Codeforces 1389B: Array Walk
6247 Codeforces 1389A: LCM Problem
6246 Codeforces 1388E: Uncle Bogdan and Projections
6245 Codeforces 1388D: Captain Flint and Treasure
6244 Codeforces 1388C: Uncle Bogdan and Country Happiness
6243 Codeforces 1388B: Captain Flint and a Long Voyage
6242 Codeforces 1388A: Captain Flint and Crew Recruitment
6241 Codeforces 1387C: Viruses
6240 Codeforces 1387B2: Village (Maximum)
6239 Codeforces 1387B1: Village (Minimum)
6238 Codeforces 1387A: Graph
6237 Codeforces 1386C: Joker
6236 Codeforces 1386B: Mixture
6235 Codeforces 1386A: Colors
6234 Codeforces 1385G: Columns Swaps
6233 Codeforces 1385F: Removing Leaves
6232 Codeforces 1385E: Directing Edges
6231 Codeforces 1385D: a-Good String
6230 Codeforces 1385C: Make It Good
6229 Codeforces 1385B: Restore the Permutation by Merger
6228 Codeforces 1385A: Three Pairwise Maximums
6227 Codeforces 1384B2: Koa and the Beach (Hard Version)
6226 Codeforces 1384B1: Koa and the Beach (Easy Version)
6225 Codeforces 1384A: Common Prefixes
6224 Codeforces 1383F: Special Edges
6223 Codeforces 1383E: Strange Operation
6222 Codeforces 1383D: Rearrange
6221 Codeforces 1383C: String Transformation 2
6220 Codeforces 1383B: GameGame
6219 Codeforces 1383A: String Transformation 1
6218 Codeforces 1382B: Sequential Nim
6217 Codeforces 1382A: Common Subsequence
6216 Codeforces 1381E: Origami
6215 Codeforces 1381D: The Majestic Brown Tree Snake
6214 Codeforces 1381C: Mastermind
6213 Codeforces 1381B: Unmerge
6212 Codeforces 1381A2: Prefix Flip (Hard Version)
6211 Codeforces 1381A1: Prefix Flip (Easy Version)
6210 Codeforces 1380G: Circular Dungeon
6209 Codeforces 1380F: Strange Addition
6208 Codeforces 1380E: Merging Towers
6207 Codeforces 1380D: Berserk And Fireball
6206 Codeforces 1380C: Create The Teams
6205 Codeforces 1380B: Universal Solution
6204 Codeforces 1380A: Three Indices
6203 Codeforces 1379F2: Chess Strikes Back (hard version)
6202 Codeforces 1379F1: Chess Strikes Back (easy version)
6201 Codeforces 1379E: Inverse Genealogy
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