You must log in or # to comment.
When you need a doubly-linked list in Python, you can use the deque data structure, which is in the collections module
When do I need a doubly-linked list in Python? Whenever I have something where I can often expect to interact with the first and last element of it? Always, because it’s more efficient than shifting the entire list around? Something else entirely?
You can use a deque as a stack (First In, Last Out) or as a queue (First In, First Out). Lists are especially inefficient when adding/removing from the beginning of the list, but, for deques, it’s a O(1) operation.