Sequences 8/2/2018 12:16 AM Linked Lists Linked Lists

Singly Linked List (§ 4.4.1) A singly linked list is a concrete data structure consisting of a sequence of nodes Each node stores element link to the next node next node elem  A B C D Linked Lists

The Node Class for List Nodes public class Node<T> extends Object { public T data; public Node<T> next; public Node () { data = null; next = null; } public Node (T val) { data = val; next = null; } } Elements: The elements are of type <Type>. Note: To implement encapsulation, we can have getter/setter of data and next here. Linked Lists

Inserting at the Head Allocate a new node Insert new element Have new node point to old head Update head to point to new node Linked Lists

Removing at the Head Update head to point to next node in the list Allow garbage collector to reclaim the former first node Linked Lists

Inserting at the Tail Allocate a new node Insert new element Have new node point to null Have old last node point to new node Update tail to point to new node Linked Lists

Removing at the Tail Removing at the tail of a singly linked list is not efficient! There is no constant-time way to update the tail to point to the previous node Linked Lists

For better understanding http://www.cs.usfca.edu/~galles/visualization/StackLL.html Linked Lists