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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)
800 Codeforces 171B: Star
799 Codeforces 171A: Mysterious numbers - 1
798 Codeforces 169B: Replacing Digits
797 Codeforces 169A: Chores
796 Codeforces 168B: Wizards and Minimal Spell
795 Codeforces 168A: Wizards and Demonstration
794 Codeforces 167E: Wizards and Bets
793 Codeforces 167D: Wizards and Roads
792 Codeforces 167C: Wizards and Numbers
791 Codeforces 167B: Wizards and Huge Prize
790 Codeforces 167A: Wizards and Trolleybuses
789 Codeforces 166E: Tetrahedron
788 Codeforces 166D: Shoe Store
787 Codeforces 166C: Median
786 Codeforces 166B: Polygons
785 Codeforces 166A: Rank List
784 Codeforces 165E: Compatible Numbers
783 Codeforces 165D: Beard Graph
782 Codeforces 165C: Another Problem on Strings
781 Codeforces 165B: Burning Midnight Oil
780 Codeforces 165A: Supercentral Point
779 Codeforces 164E: Polycarpus and Tasks
778 Codeforces 164D: Minimum Diameter
777 Codeforces 164C: Machine Programming
776 Codeforces 164B: Ancient Berland Hieroglyphs
775 Codeforces 164A: Variable, or There and Back Again
774 Codeforces 163E: e-Government
773 Codeforces 163D: Large Refrigerator
772 Codeforces 163C: Conveyor
771 Codeforces 163B: Lemmings
770 Codeforces 163A: Substring and Subsequence
769 Codeforces 162J: Brackets
768 Codeforces 162I: Truncatable primes
767 Codeforces 162H: Alternating case
766 Codeforces 162G: Non-decimal sum
765 Codeforces 162F: Factorial zeros
764 Codeforces 162E: HQ9+
763 Codeforces 162D: Remove digits
762 Codeforces 162C: Prime factorization
761 Codeforces 162B: Binary notation
760 Codeforces 162A: Pentagonal numbers
759 Codeforces 161E: Polycarpus the Safecracker
758 Codeforces 161D: Distance in Tree
757 Codeforces 161C: Abracadabra
756 Codeforces 161B: Discounts
755 Codeforces 161A: Dress'em in Vests!
754 Codeforces 160E: Buses and People
753 Codeforces 160D: Edges in MST
752 Codeforces 160C: Find Pair
751 Codeforces 160B: Unlucky Ticket
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