http://qs321.pair.com?node_id=375201


in reply to e

sub e{
    use integer;
    my @e=(1) x shift;
    for(1..@e*log(@e)/3){
        for(reverse(1..$#e)){
            $e[$_-1]+=$e[$_]/$_; $e[$_]%=$_;
        }
        printf"%01d",$e[0]; $e[0]=0;
        $_*=10 for @e;
    }
}

[download]

Replies are listed 'Best First'.
Re^2: e
by tachyon (Chancellor) on Jul 17, 2004 at 07:28 UTC

    Cool. Lovely piece of code.

    Map gets it down to 105 chars - yes void maps are good for golf only! 

    sub e{
#234567890123456789012345678901234567890123456789012
@e=(1)x pop;map{map{$e[$_-1]+=$e[$_]/$_;$e[$_]=10*($
e[$_]%$_)}reverse 1..$#e;print int$e[0];$e[0]=0}1..@e
}

# or if you prefer whitespace and no void maps
sub e{
    @e=(1)x pop;
    for(1..@e){
        for(reverse(1..$#e)){
            $e[$_-1]+=$e[$_]/$_;
            $e[$_]=10*($e[$_]%$_)
        }
        print int $e[0];
        $e[0]=0
    }
}

    [download]

    cheers

    tachyon

[reply]
[d/l]
    Re^3: e
    by mtve (Deacon) on Jul 17, 2004 at 09:36 UTC

      Simple optimizations down to 86:

      sub e{
#234567890123456789012345678901234567890123456789012
map{$e[$q-1]+=$e[$q]/$q,($e[$q]%=$q--).=0for
1..($q=@e);$e[0]=!print"@e"|0}@e=(1)x pop
}
e(1000);

      [download]

      Update from tybalt89 - 80 chars:

      $=[!print$=]=!map{$==$=[$#z]+=$=[@z]/@z,($=[@z]%=1+$#z--).=0}@z=@=for@
+==(1)x pop

      [download]
      Re^4: e
      by shmem (Chancellor) on Sep 13, 2015 at 09:47 UTC 
        $=[!print$=]=!map{$==$=[$#z]+=$=[@z]/@z,($=[@z]%=1+$#z--).=0}@z=@=for@
+==(1)x pop

        [download]

        Segfaults with perl v5.18.2: 

        qwurx [shmem] ~> perl -e '$=[!print$=]=!map{$==$=[$#z]+=$=[@z]/@z,($=[
+@z]%=1+$#z--).=0}@z=@=for@==(1)x pop' 10
Attempt to free unreferenced scalar: SV 0xdd0968, Perl interpreter: 0x
+da4010 at -e line 1.
Segmentation fault

        [download]

        Works with v5.10.1 though. Looks like the segfault happens here: 

        $=[@z]%=1+$#z--).=0

        [download]

        Can't (for now) figure out why.

        perl -le'print map{pack c,($-++?1:13)+ord}split//,ESEL'
[reply]
[d/l]
[select]

        There was a bug in the code I posted. AFAIK it does not effect the result per se just the efficiency. By trying to scrape a char by using @e instead of $#e (as used in IOs code) within the inner loop we are accessing a non existent element one past the end of the array. As a result @e is growing by one with each inner loop.

        cheers

        tachyon

[reply]

In Section Obfuscated Code