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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)
5850 Codeforces 1313E: Concatenation with intersection
5849 Codeforces 1313D: Happy New Year
5848 Codeforces 1313C2: Skyscrapers (hard version)
5847 Codeforces 1313C1: Skyscrapers (easy version)
5846 Codeforces 1313B: Different Rules
5845 Codeforces 1313A: Fast Food Restaurant
5844 Codeforces 1312G: Autocompletion
5843 Codeforces 1312F: Attack on Red Kingdom
5842 Codeforces 1312E: Array Shrinking
5841 Codeforces 1312D: Count the Arrays
5840 Codeforces 1312C: Adding Powers
5839 Codeforces 1312B: Bogosort
5838 Codeforces 1312A: Two Regular Polygons
5837 Codeforces 1311F: Moving Points
5836 Codeforces 1311E: Construct the Binary Tree
5835 Codeforces 1311D: Three Integers
5834 Codeforces 1311C: Perform the Combo
5833 Codeforces 1311B: WeirdSort
5832 Codeforces 1311A: Add Odd or Subtract Even
5831 Codeforces 1310F: Bad Cryptography
5830 Codeforces 1310E: Strange Function
5829 Codeforces 1310D: Tourism
5828 Codeforces 1310C: Au Pont Rouge
5827 Codeforces 1310B: Double Elimination
5826 Codeforces 1310A: Recommendations
5825 Codeforces 1307G: Cow and Exercise
5824 Codeforces 1307F: Cow and Vacation
5823 Codeforces 1307E: Cow and Treats
5822 Codeforces 1307D: Cow and Fields
5821 Codeforces 1307C: Cow and Message
5820 Codeforces 1307B: Cow and Friend
5819 Codeforces 1307A: Cow and Haybales
5818 Codeforces 1305H: Kuroni the Private Tutor
5817 Codeforces 1305G: Kuroni and Antihype
5816 Codeforces 1305F: Kuroni and the Punishment
5815 Codeforces 1305E: Kuroni and the Score Distribution
5814 Codeforces 1305D: Kuroni and the Celebration
5813 Codeforces 1305C: Kuroni and Impossible Calculation
5812 Codeforces 1305B: Kuroni and Simple Strings
5811 Codeforces 1305A: Kuroni and the Gifts
5810 Codeforces 1304F2: Animal Observation (hard version)
5809 Codeforces 1304F1: Animal Observation (easy version)
5808 Codeforces 1304E: 1-Trees and Queries
5807 Codeforces 1304D: Shortest and Longest LIS
5806 Codeforces 1304C: Air Conditioner
5805 Codeforces 1304B: Longest Palindrome
5804 Codeforces 1304A: Two Rabbits
5803 Codeforces 1303G: Sum of Prefix Sums
5802 Codeforces 1303F: Number of Components
5801 Codeforces 1303E: Erase Subsequences
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