Topics: Data Structure - List
A doubly linked list is a type of list. It’s very similar to a simple linked list, the only difference being the fact that each node is composed of three (instead of two) fields:
- Previous link: contains the pointer to the previous element
- Information: contains the element of the list in the node
- Next link: contains the pointer to the next element
Visually, one of these nodes can be seen as follows:
| Previous | Information | Next |
|---|
In its Previous field, the first node has a pointer that points to nothing. In its Next field, the last node has a pointer that points to nothing.
Just like in a simple linked list, it’s necessary to have a pointer variable that points to the first element of the list.