---

Introduction: recursive algorithms and linked lists

---

• The list structure revisited
  • Recall that a linked list is a chained of List object.

  • We usually use a reference variable called head to point to the first List object in the chain

    Example: linked list

    ---

    ---

  • Notice that the linked list structure is a recursive structure

    I.e.: a linked list contains another (smaller) linked list

    Example: a linked list of 5 elements contains a linked list of 4 elements

    ---

    ---

  • Important consequence of the recursive nature of linked lists:

    In general: Recursive algorithms works best on problems/structures that can be defined recurisvely Since a linked list is (by its nature) a recursive data structure, you can expect that recursive algorithms will very very well (and simple) on linked list

    I will illustrate this with a look up and an insertion algorithm on linked list.

    And you can practice recursion on linked list in a project assignment (insert into an ordered list)