I am used to seeing ring buffers implemented using an array. They are FIFO if you write to the maximum offset and read from the minimum offset but they are double ended if you have a method to read from the maximum offset and write to the minimum offset.
No that’s a subtly different thing. The storage is a contiguous vector, but because it is a ring buffer there must be one pair of adjacent elements that are not contiguous in memory. That’s what that comment is saying.
But because it is only one discontinuity it doesn’t affect algorithmic complexity, so it is still O(1) to access elements, unlike a linked list which is O(N).
If you google “circular buffer” there will be loads of diagrams that make it really obvious how it works.
But a ring buffer is a FIFO data structure that can be implemented using linked lists. What ring buffer implementation did you have in mind?
I am used to seeing ring buffers implemented using an array. They are FIFO if you write to the maximum offset and read from the minimum offset but they are double ended if you have a method to read from the maximum offset and write to the minimum offset.
Standard ring buffers or circular buffers are implemented as continuous vectors, with a read and write pointer.
Rust’s
VecDequeis a ring buffer: https://doc.rust-lang.org/std/collections/struct.VecDeque.htmlNo that’s a subtly different thing. The storage is a contiguous vector, but because it is a ring buffer there must be one pair of adjacent elements that are not contiguous in memory. That’s what that comment is saying.
But because it is only one discontinuity it doesn’t affect algorithmic complexity, so it is still O(1) to access elements, unlike a linked list which is O(N).
If you google “circular buffer” there will be loads of diagrams that make it really obvious how it works.