Beefy Boxes and Bandwidth Generously Provided by pair Networks
Keep It Simple, Stupid
 
PerlMonks  

Re: Fibonacci golf with one state variable

by JavaFan (Canon)
on Oct 05, 2008 at 11:43 UTC ( [id://715421]=note: print w/replies, xml ) Need Help??


in reply to Fibonacci golf with one state variable

Without eval, without quotes, without explicit assignment and without arithmetic:
perl -lE 's//:o/;say length$1 while s/(.*):(.*)/$2:$1$2/'

Replies are listed 'Best First'.
Re^2: Fibonacci golf with one state variable
by aufflick (Deacon) on Oct 05, 2008 at 11:54 UTC

    Hey that's neat! Of course the memory usage is far from constant, but great idea. Good use of say to save a few.

    Only nitpicks are that you do have explicit initialisation and the first output is zero which is not quite right. Oddly, I get no output unless I tweak it to print to STDERR which is some strange buffering difference - no idea why.

    ++ for thinking laterally :)

      Well, I'd argue that *not* outputting zero isn't quite right. Usually, the Fibonacci sequence is defined as F(0) = 0; F(1) = 1; F(n) = F(n-1) + F(n-2), n > 1. See for instance Sloane: The On-Line Encyclopedia of Integer Sequences and Graham, Knuth and Patashnik in Concrete Mathematics. Eric Weisstein defines the sequence as starting with F(1) = F(2) = 1 and then states it's conventional to define F(0) = 0.
        Can't fault your references!
Re^2: Fibonacci golf with one state variable
by ikegami (Patriarch) on Oct 05, 2008 at 12:18 UTC

    Heh! I had come up with exactly that! It's not shorter, though. And boy does it get slow fast.

    Save a char by dropping the "l" in "-lE".
    Save a char by dropping the space after "-E".

Re^2: Fibonacci golf with one state variable
by ambrus (Abbot) on Oct 15, 2009 at 17:39 UTC

Log In?
Username:
Password:

What's my password?
Create A New User
Domain Nodelet?
Node Status?
node history
Node Type: note [id://715421]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this?Last hourOther CB clients
Other Users?
Others drinking their drinks and smoking their pipes about the Monastery: (3)
As of 2024-03-29 04:33 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    No recent polls found