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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)
1450 Codeforces 327B: Hungry Sequence
1449 Codeforces 327A: Flipping Game
1448 Codeforces 325E: The Red Button
1447 Codeforces 325D: Reclamation
1446 Codeforces 325C: Monsters and Diamonds
1445 Codeforces 325B: Stadium and Games
1444 Codeforces 325A: Square and Rectangles
1443 Codeforces 323C: Two permutations
1442 Codeforces 323B: Tournament-graph
1441 Codeforces 323A: Black-and-White Cube
1440 Codeforces 322B: Ciel and Flowers
1439 Codeforces 322A: Ciel and Dancing
1438 Codeforces 321E: Ciel and Gondolas
1437 Codeforces 321D: Ciel and Flipboard
1436 Codeforces 321C: Ciel the Commander
1435 Codeforces 321B: Ciel and Duel
1434 Codeforces 321A: Ciel and Robot
1433 Codeforces 320B: Ping-Pong (Easy Version)
1432 Codeforces 320A: Magic Numbers
1431 Codeforces 319E: Ping-Pong
1430 Codeforces 319D: Have You Ever Heard About the Word?
1429 Codeforces 319C: Kalila and Dimna in the Logging Industry
1428 Codeforces 319B: Psychos in a Line
1427 Codeforces 319A: Malek Dance Club
1426 Codeforces 318B: Strings of Power
1425 Codeforces 318A: Even Odds
1424 Codeforces 317E: Princess and Her Shadow
1423 Codeforces 317D: Game with Powers
1422 Codeforces 317C: Balance
1421 Codeforces 317B: Ants
1420 Codeforces 317A: Perfect Pair
1419 Codeforces 316G3: Good Substrings
1418 Codeforces 316G2: Good Substrings
1417 Codeforces 316G1: Good Substrings
1416 Codeforces 316F3: Suns and Rays
1415 Codeforces 316F2: Suns and Rays
1414 Codeforces 316F1: Suns and Rays
1413 Codeforces 316E3: Summer Homework
1412 Codeforces 316E2: Summer Homework
1411 Codeforces 316E1: Summer Homework
1410 Codeforces 316D3: PE Lesson
1409 Codeforces 316D2: PE Lesson
1408 Codeforces 316D1: PE Lesson
1407 Codeforces 316C2: Tidying Up
1406 Codeforces 316C1: Tidying Up
1405 Codeforces 316B2: EKG
1404 Codeforces 316B1: EKG
1403 Codeforces 316A2: Special Task
1402 Codeforces 316A1: Special Task
1401 Codeforces 315B: Sereja and Array
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