Re: golf help needed.

Alex:  Thats the cutest thing I've seen in a while!  Sorry, but
I don't have any immediate suggestions.  In order to get it to work on
my (pretty fast) linux box, I had to add another '9' to your timing
9x9999999 thingy...

Thanks for brightening my morning...

--Doug Hunt


On Wed, 12 Nov 2003 [email protected] wrote:

> Hi all, first time poster etc etc.  I'm a lurker on london pm and play
> around on the obfu forum of perlmonks from time to time (as
> teamster_jr)...
> 
> anyway.  I've just finished this, i hope y'all like it:
> 
> @m=((31,(15)x8)x8,(31)x9);$m[$c]|=16,!(@a=grep/-?./&!(16+$|*$'&$m[$c+$&]
> ),-18,11,94,-92)?$c=pop@p:${$_=$a[rand@a];s/-?.//;push@p,$c;$m[$c]&=~8/$
> _;++$u-64?$m[$c+=$&]&=~$_:map$_&=15,@m,$c=$|=1},$|&&9x9999999,print"\ec"
> ,map$_%9?($_-$c?$m[$_]&2?_:$":o).($m[$_]&8?"|":_):$/,1..72until$c>70&$|
> 
> apologies if someone else has done it before...
> 
> which whilst i'm glad to have finished (thanks to some peeps on perlmonks
> - especially mtve)  - ie get down to <288 chars (it started off as two 4
> line sigs - one to generate and one to solve), i'm not entirely happy with
> it - i had to make lots of concessions to get it to that size (including
> an utterly horrible hack to replace a select timing call - 9x999999 which
> takes ~.1 s on my machine but YMMV if it works at all (i think it works by
> just packing out the code, but i'm not sure!).
> 
> so i was wondering if you guys could have a look at the original code and
> see if there's a way of golfing it down whilst keeping some more of the
> features...
> 
> @m=((31,(15)x15)x10,(31)x16);$m[$c]|=16,!(@a=grep!($m[$c+$$_[0]]&16+$s*$
> $_[1]),[-1,8],[1,1],[16,4],[-16,2])?$c=pop@p:${($i,$j)=@{$a[rand@a]};$m[
> $c]&=~8/$j;push@p,$c;$m[$c+=$i]&=~$j;++$u-150||map$_&=15,@m,$c=$s=1},$s&
> &select$x,$x,$x,.1*print"\ec",(_)x31,map$_%16?($_-$c?$m[$_]&2?_:$":o).($
> m[$_]&8?"|":_):"$/|",0..160until$c>158&$s
> 
> 
> and here's some commented unpacked code:
> 
> #!/usr/bin/perl
> # this uses depth first search to generate and solve maze.
> #   4           16 = visited
> # 8   1
> #   2
> 
> # m is array of 5 bit numbers:
> # bit 1= right
> # 2= down
> # 3= up
> # 4= left
> # 5= visited
> 
> # search is looking for where visited and
> # (direction & s - second pass flag) are unset
> 
> # set up maze - border is set as visited. all direction bits set.
> @m=((31,(15)x15)x10,(31)x16);
> 
> # we now start an until loop - which continues till end of second pass
> 
> # set visited bit on current square
> $m[$c]|=16,
> 
> !(
> # search for available options (first part is direction difference,
> # second is direction bit
> 
> @a=grep!($m[$c+$$_[0]]&16+$s*$$_[1]),
> [-1,8],[1,1],[16,4],[-16,2]
> )?
> 
> # if it's none available then go back
> $c=pop@p:
> ${
> # otherwise chose random direction
> ($i,$j)=@{$a[rand@a]};
> 
> # unset the current bit with the direction
> $m[$c]&=~8/$j;
> # add current position to stack
> push@p,$c;
> 
> # unset next square's direction bit
> $m[$c+=$i]&=~$j;
> 
> # if we've visited all the squares, then unset visited bit,
> # reset position and set flag for second pass (ie turn on
> # direction checking in search func).
> 
> ++$u-150||map$_&=15,@m,$c=$s=1
> 
> },
> 
> # if we're on second pass draw it (with pause between draws)
>  $s&&
> select$x,$x,$x,.1*print"\ec",
> (_)x31,
> 
> map$_%16?
> ($_-$c?$m[$_]&2?_:$":o).
> ($m[$_]&8?"|":_):
> "$/|",
> 
> 0..160
> # until we get to bottom right.
> until$c>158&$s
> 
> ## end code
> 
> well, if you've got this far.  Thanks a lot.
> 
> Alex
> 

-- 
[email protected]
Software Engineer III
UCAR - COSMIC, Tel. (303) 497-2611