How to implement an addressable FIFO queue?

Question

I'm currently looking for a data structure with all O(1) operations

• insert(K, V): Insert a value at the end of the queue.
• remove_key(K): Remove the value from the queue corresponding to the provided key.
• remove_head(): Remove the value from the front of the queue (the oldest one).

The only reasonably easy to implement thing I can think of is using a doubly linked list as the primary data structure, and keeping pointers to the list nodes in a hash table, which would get the desired asymptotic behavior, however this might not be the most efficient option in actual runtime.

I found "addressable priority queues" in the literature, but they are rather complicated (and maybe even more expensive) data structures, so I was wondering if someone has a better suggestion. It seems no one implemented something like this for Rust so far, which is why I'm hoping it doesn't get too complicated.

Answer 1

I would use a pub struct VecDeque<T> and use pop_front() instead of remove_head() .

See the doc: VecDeque

Answer 2

这里我用Python实现了一个Addressable Binary Heap ，没有第三方依赖。