Can you explain what a circular data structure is and how it works?

A circular data structure (or circular buffer) is a structure that uses a fixed-size array as a ring, where the end is connected to the beginning.

It works so that when the end of the array is reached, the next element will be written at the beginning if there is free space. This allows efficient use of memory for queues or buffers, where data is written and read in a circular manner.

For example, in the implementation of a queue using a circular buffer, there are two pointers: one at the start and one at the end. When adding an element, the end pointer moves forward; when removing, the start pointer moves forward. If the pointers coincide, the buffer can be either empty or full, depending on the implementation.

This approach is useful for streaming data processing, where it is important to limit the buffer size and avoid constant memory allocation.