http://qs321.pair.com?node_id=270362


in reply to Alpha base-26 to base-10...

Feel free to not use the name:) 

sub b262b10{ my ($n,$x)=(0,'A'); ++$n until $x++ eq $_[0]; ++$n }

print $_, ':', b262b10( $_ ), $/ for qw[A Z AA AZ BA ZZ AAA ZBA]
A : 1
Z : 26
AA : 27
AZ : 52
BA : 53
ZZ : 702
AAA : 703
ZBA : 17629

[download]

Update: Lest anyone not realise it, this okay as a golf solution, but it is not a serious contender for anything real as it is horribly inefficient.

Examine what is said, not who speaks.
"Efficiency is intelligent laziness." -David Dunham
"When I'm working on a problem, I never think about beauty. I think only how to solve the problem. But when I have finished, if the solution is not beautiful, I know it is wrong." -Richard Buckminster Fuller


Replies are listed 'Best First'.
Re: Re: Alpha base-26 to base-10... (golf)
by sauoq (Abbot) on Jul 01, 2003 at 03:48 UTC

    Did you say "golf"? :-)

                          1         2
             123456789012345678901234567
sub b262b10{ my$n;$n++for"a"..lc$_[0];$n }

    [download]

    27

    Update: Make that 26. I can save a stroke by reusing @_. :-)

    sub b262b10{ $_[1]++for"a"..lc$_[0];pop }

    [download]
    -sauoq
"My two cents aren't worth a dime.";
[reply]
[d/l]
[select]
      Golf? 
      sub b262b10{ ()=a..lc pop }

      [download]

      Explanation:

      In Golf, there's no need for strict or quotes. A bareword is a string when Perl can't find an identifier with that name. So here, a is just "a", only two strokes shorter.

      pop takes one argument off of @_, and since there's only one argument, it's just the same as shift. lc turns it to lower case.

      .. is the range operator in list context, but the flip-flop operator in scalar context. The construct ()= forces list context. The value of a list assignment is the number of elements of the right member, even though the left value (()) is empty.

      So this sub yields (in scalar context) the number of element between "a" and the string passed as argument. QED

      --bwana147

[reply]
[d/l]
[select]
        what?

        Care to explain that?

[reply]

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