When do you use "if ( a = b )"? (was Re: Funny mistake)

[Sven Heinicke]

In <65837 at eerie.acsu.Buffalo.EDU>, chu at acsu.buffalo.edu writes:
>In article <775 at camco.Celestial.COM> bill at camco.Celestial.COM (Bill Campbell) writes:
>[concerning "if ( a = b )"
>
>It's been my mistake everytime I've done it!! I realize that it is a
>legal construction and I know what it does, but I was wondering...
>Is there a good use for this?
>

I went through some of the programs that I wrote and here is probely
the best example of a good use for it that was kind of easy to
understand (if finds the greatest common demonator of a and b).  You
can write the program without in in the while statment but it was the
easest place I could find to put it.

int gcd(a,b)
     int a,b;
{ 
  int r,q;

  while(r = a%b)
    {
       q = a/b;
       a = b;
       b = r;
    }
  return(b);
}

-- 
sven at cs.widener.edu                                  Widener CS system manager
Sven Mike Heinicke                                          and Student
(pssmheinicke at cyber.widener.edu (if you must))