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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)
7105 Codeforces 1553F: Pairwise Modulo
7104 Codeforces 1553E: Permutation Shift
7103 Codeforces 1553D: Backspace
7102 Codeforces 1553C: Penalty
7101 Codeforces 1553B: Reverse String
7100 Codeforces 1553A: Digits Sum
7099 Codeforces 1552I: Organizing a Music Festival
7098 Codeforces 1552H: Guess the Perimeter
7097 Codeforces 1552G: A Serious Referee
7096 Codeforces 1552F: Telepanting
7095 Codeforces 1552E: Colors and Intervals
7094 Codeforces 1552D: Array Differentiation
7093 Codeforces 1552C: Maximize the Intersections
7092 Codeforces 1552B: Running for Gold
7091 Codeforces 1552A: Subsequence Permutation
7090 Codeforces 1551F: Equidistant Vertices
7089 Codeforces 1551E: Fixed Points
7088 Codeforces 1551D2: Domino (hard version)
7087 Codeforces 1551D1: Domino (easy version)
7086 Codeforces 1551C: Interesting Story
7085 Codeforces 1551B2: Wonderful Coloring - 2
7084 Codeforces 1551B1: Wonderful Coloring - 1
7083 Codeforces 1551A: Polycarp and Coins
7082 Codeforces 1550F: Jumping Around
7081 Codeforces 1550E: Stringforces
7080 Codeforces 1550D: Excellent Arrays
7079 Codeforces 1550C: Manhattan Subarrays
7078 Codeforces 1550B: Maximum Cost Deletion
7077 Codeforces 1550A: Find The Array
7076 Codeforces 1549B: Gregor and the Pawn Game
7075 Codeforces 1549A: Gregor and Cryptography
7074 Codeforces 1548E: Gregor and the Two Painters
7073 Codeforces 1548D2: Gregor and the Odd Cows (Hard)
7072 Codeforces 1548D1: Gregor and the Odd Cows (Easy)
7071 Codeforces 1548C: The Three Little Pigs
7070 Codeforces 1548B: Integers Have Friends
7069 Codeforces 1548A: Web of Lies
7068 Codeforces 1547G: How Many Paths?
7067 Codeforces 1547F: Array Stabilization (GCD version)
7066 Codeforces 1547E: Air Conditioners
7065 Codeforces 1547D: Co-growing Sequence
7064 Codeforces 1547C: Pair Programming
7063 Codeforces 1547B: Alphabetical Strings
7062 Codeforces 1547A: Shortest Path with Obstacle
7061 Codeforces 1546B: AquaMoon and Stolen String
7060 Codeforces 1546A: AquaMoon and Two Arrays
7059 Codeforces 1545F: AquaMoon and Potatoes
7058 Codeforces 1545E2: AquaMoon and Time Stop (hard version)
7057 Codeforces 1545E1: AquaMoon and Time Stop (easy version)
7056 Codeforces 1545D: AquaMoon and Wrong Coordinate
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