Editing Association list (section)

==Performance==
The disadvantage of association lists is that the time to search is {{math|[[Big O notation|''O''(''n'')]]}}, where {{mvar|n}} is the length of the list.<ref>{{cite book|first=Donald|last=Knuth|author-link=Donald Knuth|contribution=6.1 Sequential Searching|title=[[The Art of Computer Programming]], Vol. 3: Sorting and Searching|date=1998 |pages=396–405|publisher=Addison Wesley|edition=2nd|isbn=0-201-89685-0}}</ref> For large lists, this may be much slower than the times that can be obtained by representing an associative array as a [[binary search tree]] or as a [[hash table]].
Additionally, unless the list is regularly pruned to remove elements with duplicate keys, multiple values associated with the same key will increase the size of the list, and thus the time to search, without providing any compensatory advantage.

One advantage of association lists is that a new element can be added in constant time. Additionally, when the number of keys is very small, searching an association list may be more efficient than searching a binary search tree or hash table, because of the greater simplicity of their implementation.<ref>{{cite book|title=Developer's Guide to Collections in Microsoft .NET|first=Calvin|last=Janes|publisher=Pearson Education|year=2011|isbn=9780735665279|page=191|contribution-url=https://books.google.com/books?id=-KdCAwAAQBAJ&pg=PT191|contribution=Using Association Lists for Associative Arrays}}</ref>