Design a hit counter that records hits and retrieves the number of hits in the past 5 minutes. You need to implement methods to record a hit and get the total hits in a sliding window.

Implement a Tic-Tac-Toe game where players take turns placing their marks. Design the game logic to efficiently determine the winner after each move.

Convert an IP address and a number of addresses to a CIDR block representation. Find the smallest list of CIDR blocks that covers the specified range of IP addresses.