Technology Fundamentals
Linked List
Definition
A linked list is a linear collection of data elements whose order is not given by their physical placement in memory. Instead, each element points to the next. It is a data structure consisting of a collection of nodes which together represent a sequence.
Why It Matters
Linked lists are a flexible alternative to arrays. They excel at insertions and deletions in the middle of the list, as you only need to update a few pointers, whereas in an array you would have to shift many elements.
Contextual Example
A music playlist can be implemented as a linked list. Each song is a node that points to the next song in the list. It's easy to insert a new song anywhere in the playlist or remove one.
Common Misunderstandings
- Accessing an element in a linked list by its index is slow (O(n) time), because you have to traverse the list from the beginning. In contrast, arrays have fast O(1) index access.
- There are different types, like singly linked lists (points forward only) and doubly linked lists (points forward and backward).