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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)
1650 Codeforces 374B: Inna and Nine
1649 Codeforces 374A: Inna and Pink Pony
1648 Codeforces 373B: Making Sequences is Fun
1647 Codeforces 373A: Collecting Beats is Fun
1646 Codeforces 372E: Drawing Circles is Fun
1645 Codeforces 372D: Choosing Subtree is Fun
1644 Codeforces 372C: Watching Fireworks is Fun
1643 Codeforces 372B: Counting Rectangles is Fun
1642 Codeforces 372A: Counting Kangaroos is Fun
1641 Codeforces 371E: Subway Innovation
1640 Codeforces 371D: Vessels
1639 Codeforces 371C: Hamburgers
1638 Codeforces 371B: Fox Dividing Cheese
1637 Codeforces 371A: K-Periodic Array
1636 Codeforces 370E: Summer Reading
1635 Codeforces 370D: Broken Monitor
1634 Codeforces 370C: Mittens
1633 Codeforces 370B: Berland Bingo
1632 Codeforces 370A: Rook, Bishop and King
1631 Codeforces 369E: Valera and Queries
1630 Codeforces 369D: Valera and Fools
1629 Codeforces 369C: Valera and Elections
1628 Codeforces 369B: Valera and Contest
1627 Codeforces 369A: Valera and Plates
1626 Codeforces 368B: Sereja and Suffixes
1625 Codeforces 368A: Sereja and Coat Rack
1624 Codeforces 367E: Sereja and Intervals
1623 Codeforces 367D: Sereja and Sets
1622 Codeforces 367C: Sereja and the Arrangement of Numbers
1621 Codeforces 367B: Sereja ans Anagrams
1620 Codeforces 367A: Sereja and Algorithm
1619 Codeforces 366E: Dima and Magic Guitar
1618 Codeforces 366D: Dima and Trap Graph
1617 Codeforces 366C: Dima and Salad
1616 Codeforces 366B: Dima and To-do List
1615 Codeforces 366A: Dima and Guards
1614 Codeforces 365B: The Fibonacci Segment
1613 Codeforces 365A: Good Number
1612 Codeforces 364E: Empty Rectangles
1611 Codeforces 364D: Ghd
1610 Codeforces 364C: Beautiful Set
1609 Codeforces 364B: Free Market
1608 Codeforces 364A: Matrix
1607 Codeforces 363E: Two Circles
1606 Codeforces 363D: Renting Bikes
1605 Codeforces 363C: Fixing Typos
1604 Codeforces 363B: Fence
1603 Codeforces 363A: Soroban
1602 Codeforces 362E: Petya and Pipes
1601 Codeforces 362D: Fools and Foolproof Roads
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