NetNews Usenet Archive 1992 #26/NN_1992_26.iso/spool/comp/lang/c/16133

Text File | 1992-11-08 | 1.7 KB | 44 lines

Newsgroups: comp.lang.c
Path: sparky!uunet!portal!dfuller
From: [e-mail] (Dave Fuller)
Subject: Re: To Recurse or NOT to recurse?
Message-ID: <[e-mail]>
Organization: VideOcart Inc.
X-Newsreader: Tin 1.1 PL3
References: <[e-mail]>
Date: Fri, 6 Nov 1992 22:28:43 GMT
Lines: 32

[e-mail] (Stephen Schow) writes:
: What is better to do when traversing a linked list..... SHould I use recursion
: to search down through the list for the last node, or should I use a while
: loop?  What or the pro's and con's of each?
:
: Thanks in advance
: ------------------------------------------------------------------
Stephen,
  If you only want to get to the end of the linked list, definitely use
a while loop. Recursion in a linked list would eat up alot of stack space
and funtion calling overhead for such a simple process.

Recursion would, however, be the choice if you need to do an operation that
needs to keep a state constant. Menuing functions are good examples of this.
If one menu calls another, you want the first one to remain in the same state
when the second one gets aborted and the first one becomes active again.
Without recursion, this would be a mess to try to keep all of the
information active in one instance of a function. Instead, you let
each instance keep track of only what it needs to.

although there probably are exceptions, the only good time for recursion
is when code will be reused and needs to keep each state of its instance
completely independant of the others.

back-and-forth wandering through the linked list would be a good case for
this, but just locating the end of the list would be much easier and
faster with a while loop.

dave fuller
[e-mail]