DequeaddFirste

DequeaddFirste is, in this article, a term used to describe the operation of inserting an element at the front of a double-ended queue (deque). The term is not standard in major programming libraries and may appear as a typographical variant or within hypothetical or educational contexts to illustrate the add-to-front operation.

Semantics: When invoked with element x, DequeaddFirste inserts x at the front, making x the first element; existing elements shift backward (in array-backed implementations) or pointers are updated (in linked-list-backed implementations).

Complexity: For a linked-list deque, the operation is O(1). For array-based deques using a circular buffer, it is also O(1) amortized, assuming no resizing. If the underlying storage is full, a resize may incur O(n) time, but subsequent insertions remain O(1). Space complexity is O(1) extra beyond the element itself, plus the underlying storage.

Comparison: In common libraries, analogous methods are addFirst in Java's Deque, push in some stack implementations, or appendleft in Python's collections.deque. The exact name DequeaddFirste is not standard.

See also: Deque, addFirst, appendleft, push, circular buffer.