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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)
7850 Codeforces 1692F: 3SUM
7849 Codeforces 1692E: Binary Deque
7848 Codeforces 1692D: The Clock
7847 Codeforces 1692C: Where's the Bishop?
7846 Codeforces 1692B: All Distinct
7845 Codeforces 1692A: Marathon
7844 Codeforces 1691F: K-Set Tree
7843 Codeforces 1691E: Number of Groups
7842 Codeforces 1691D: Max GEQ Sum
7841 Codeforces 1691C: Sum of Substrings
7840 Codeforces 1691B: Shoe Shuffling
7839 Codeforces 1691A: Beat The Odds
7838 Codeforces 1690G: Count the Trains
7837 Codeforces 1690F: Shifting String
7836 Codeforces 1690E: Price Maximization
7835 Codeforces 1690D: Black and White Stripe
7834 Codeforces 1690C: Restoring the Duration of Tasks
7833 Codeforces 1690B: Array Decrements
7832 Codeforces 1690A: Print a Pedestal (Codeforces logo?)
7831 Codeforces 1689E: ANDfinity
7830 Codeforces 1689D: Lena and Matrix
7829 Codeforces 1689C: Infected Tree
7828 Codeforces 1689B: Mystic Permutation
7827 Codeforces 1689A: Lex String
7826 Codeforces 1688C: Manipulating History
7825 Codeforces 1688B: Patchouli's Magical Talisman
7824 Codeforces 1688A: Cirno's Perfect Bitmasks Classroom
7823 Codeforces 1687F: Koishi's Unconscious Permutation
7822 Codeforces 1687E: Become Big For Me
7821 Codeforces 1687D: Cute number
7820 Codeforces 1687C: Sanae and Giant Robot
7819 Codeforces 1687B: Railway System
7818 Codeforces 1687A: The Enchanted Forest
7817 Codeforces 1686B: Odd Subarrays
7816 Codeforces 1686A: Everything Everywhere All But One
7815 Codeforces 1685E: The Ultimate LIS Problem
7814 Codeforces 1685D2: Permutation Weight (Hard Version)
7813 Codeforces 1685D1: Permutation Weight (Easy Version)
7812 Codeforces 1685C: Bring Balance
7811 Codeforces 1685B: Linguistics
7810 Codeforces 1685A: Circular Local MiniMax
7809 Codeforces 1684H: Hard Cut
7808 Codeforces 1684G: Euclid Guess
7807 Codeforces 1684F: Diverse Segments
7806 Codeforces 1684E: MEX vs DIFF
7805 Codeforces 1684D: Traps
7804 Codeforces 1684C: Column Swapping
7803 Codeforces 1684B: Z mod X = C
7802 Codeforces 1684A: Digit Minimization
7801 Codeforces 1682F: MCMF?
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