views:

51132

answers:

66

The challenge

The shortest code by character count that will output the numeric equivalent of an Excel column string.

For example, the A column is 1, B is 2, so on and so forth. Once you hit Z, the next column becomes AA, then AB and so on.

Test cases:

A:    1
B:    2
AD:   30
ABC:  731
WTF:  16074
ROFL: 326676

Code count includes input/output (i.e full program).

+29  A: 

Ruby 1.8.7, 53 50 46 44 24 17 characters

p ('A'..$_).count

Usage:

$ echo -n ROFL | ruby -n a.rb
326676
$ echo -n WTF | ruby -n a.rb
16074
$ echo -n A | ruby -n a.rb
1
Mark Rushakoff
Great, I tested very similar pattern already, but I didnt realize that `p (` and `p(` is different, :(
S.Mark
use `echo -n ...` so you can drop the `.chop`
gnibbler
Looks like I may have to start learning Ruby! :)
David
And I thought Perl was unreadable ;)
Vivin Paliath
@gnibbler: Thanks for the -n idea, that brings my perl solution down to 17 as well.
David
You could get that to 16 by using ?A instead of 'A'
steenslag
+1  A: 

Perl, 120 characters

chomp($n=<>);@c=split(//,uc($n));$o=64;$b=0;$l=$#c;for($i=$l;$i>=0;$i--){$b+=((26**($l-$i))*(ord($c[$i])-$o));}print$b;

Usage:

[email protected] ~/Projects/code/perl/excelc
$ echo WTF | perl e.pl
16074
[email protected] ~/Projects/code/perl/excelc
$ echo ROFL | perl e.pl
326676

I'm sure some of the Perl gurus here can come up with something way smaller.

Vivin Paliath
+1  A: 

Perl, 47 characters (from stdin)

chop($l=<>);$_=A;$.++,$_++while$_ ne$l;die$.,$/
hobbs
That's a neat trick! Can you explain how you did it? This is actually the first code golf I've ever tried and I'm not familiar with all the tricky stuff you can do in Perl.
Vivin Paliath
It's abusing the magic thing the `++` operator does on strings -- see `perldoc perlop` and search "little extra builtin magic". I'll write a more thorough explanation after I take care of some business at work.
hobbs
A: 

Python

import string

letters = string.uppercase
colnum = lambda s: sum((letters.index(let)+1)*26**idx for idx, let in enumerate(s[::-1]))

print colnum('WTF') 
# 16074
print colnum('ROFL')
# 326676
ars
I dunno about you, but I find that a lot easier to understand than the Perl solution that has almost 2x the characters. +1 for Python-love.
BlueRaja - Danny Pflughoeft
+4  A: 

Perl, 34 characters

map$\=26*$\-64+ord,pop=~/./g;print

Thanks to mobrule for several suggestions.

Kinopiko
You can say `pop=~/./g` instead of `split//,$ARGV[0]`You can omit the `$_` in the `ord` call.You can use `$\` instead of `$s` and then just say `print`.
mobrule
+8  A: 

JavaScript 1.8: 68 characters

function a(p)[].reduce.call(p,function(t,d)t*26+d.charCodeAt()-64,0)

Javascript 1.8: 72 characters

function a(p)(t=0,p.replace(/./g,function(d)t=t*26+d.charCodeAt()-64),t)

JavaScript 1.6: 83 characters

function a(p){t=0;p.split("").map(function(d){t=t*26+d.charCodeAt(0)-64});return t}

JavaScript: 95 characters

function a(p){r=0;t=1;l=p.length;for(i=0;i<l;i++){r+=(p.charCodeAt(l-1-i)-64)*t;t*=26}return r}

JavaScript: 105 characters

function a(p,i){i=i||0;l=p.length;return p?(p.charCodeAt(l-1)-64)*Math.pow(26,i)+a(p.slice(0,l-1),i+1):0}

Usage:

a("A")        // 1
a("B")        // 2
a("AD")       // 30
a("ABC")      // 731
a("WTF")      // 16074
a("ROFL")     // 326676
Daniel Vassallo
@Ates: Nice trick! I like map() :)
Daniel Vassallo
Thanks! I shaved 2 more characters from your solution.
Ates Goral
I shaved 4 more characters from the 1.6 solution using expression closures. You may be able to shrink it a bit more by refactoring the `(t?g*26:0)` part.
David Murdoch
UPDATE. I just shaved off 9 more characters by using [].reduce
David Murdoch
FWIW, I added an implementation using `string#replace`
Chetan Sastry
@Chetan, @David: Good job. That's neat!
Daniel Vassallo
+11  A: 

C# 156 146 118 Chars

using System.Linq;class P{static void Main(string[]a){System.Console.Write(
a[0].Aggregate(0,(t,c)=>(t+c-64)*26)/26);}}

Ungolfed:

using System.Linq;
class P
{
    static void Main(string[] a)
    {
        System.Console.Write(a[0]
            .Aggregate(0, (t, c) => (t + c - 64) * 26) / 26);
    }
}
Cameron MacFarland
The using C=System.Console shortcut isn't helping you here, because you end up having to say "System." twice. You can save 5 chars if you just do "using System;" and change your code accordingly. But my non-linq version is still shorter. :)
Charles
You're right, and I can make it shorter still by using the first argument instead of Console.Readline, making it shorter still. :P
Cameron MacFarland
oh crap, I helped you get ahead of me! :P
Charles
By the way, thanks for fixing my char count. I totally spaced on that.
Charles
How about `Console.Write` instead of `WriteLine` ?
Andreas Grech
You can avoid use of Math.Pow() using Horner's Rule (see my answer)
Daniel Renshaw
Thanks for the help! :)
Cameron MacFarland
You can probably shave off a few chars by invoking Aggregate() as a normal method which has the net effect of eliminating a `using` keyword.
erikkallen
@erikkallen - Tried that, it's a few characters longer. using < Enumerable
Cameron MacFarland
Think you may write the function itself only, without usings, classes and etc.
Kamarey
+85  A: 

Perl, 36 34 33 31 30 17 15 11 characters

$_=()=A..$_

Usage:

$ echo -n WTF | perl -ple '$_=()=A..$_'
16074

Reduced to 17 by using echo -n to avoid a chop call.

Reduced to 15 by using say instead of print.

Reduced to 11 by using -p instead of say.

Explanation: A is evaluated in string context and A..$_ builds a list starting at "A" and string-incrementing up to the input string. Perl interprets the ++ operator (and thus ..) on strings in an alphabetic context, so for example $_="AZ";$_++;print outputs BA.

=()= (aka "goatse" operator) forces an expression to be evaluated in list context, and returns the number of elements returned by that expression i.e., $scalar = () = <expr> corresponds to @list = <expr>; $scalar = @list.

David
Use `$_` or `$\` instead of `$n` and call `print` with no args.
mobrule
@mobrule: Thanks! That drops a character.
David
I meant `$\ `, not `$\`` (markup error)
mobrule
use "-p" and drop print altogether : echo -n WTF | perl -p -e '$_=()=A..$_' Total code : 11 characters, AH AH!
wazoox
switch `print` to `say` and drop another 2 characters :)
mpeters
@wazoox, that doesn't work for me - it hangs since there's no \n in the input.
David
Ah I love the goatse operator :)
Ether
Hey, Perl beats J!
David
So it does... now Perl is the winner (for now) :)
Vivin Paliath
You can drop `-n` if you use `-l` here.
J.F. Sebastian
You know, in even in the spirit of the competition, when the command to call your code is longer than the code itself I don't think it counts :-p
Kragen
Yeah, I still think the J solution is more elegant. :)
David
There is only a limited amount of 11 character perl programs that will actually compile... makes me wonder what the other ones do.
Dan
+1 for goatse operator
fahadsadah
Looks like 40 characters to me.
AMissico
+1  A: 

Java, 164 characters

public class A{public static void main(String[] z){int o=0,c=0;for(int i=z[0].length()-1;i>=0;i--,c++)o+=(z[0].charAt(i)-64)*Math.pow(26,c);System.out.println(o);}}

Java, 177 characters

public class A
{
public static void main(String[] z)
{
    int m,o=0,c=0;
    for(int i=z[0].length()-1;i>=0;i--,c++)
    {
        m=(int)Math.pow(26,c);
        o+=(z[0].charAt(i)-64)*m;
    }
    System.out.println(o);
}
}

Assumes an uppercase input (via command line argument). The obvious approach with no tricks.

Ross
+4  A: 

C89, 58 characters

s;main(c){while(c=getchar()+1)s=26*s+c-65;printf("%d",s);}

The input (stdin) must contain only A-Z, no other characters (including newlines) are allowed.

Adam Rosenfield
`getchar()` returns `< 0` on EOF; EOF is not defined as -1, but it's common.
strager
@strager: Good point. Ensuring full portability would then require adding 2 characters (by changing `c=getchar()+1` to `(c=getchar())>=0` and `65` to `64`). But, this should work in almost any C implementation.
Adam Rosenfield
+9  A: 

Python, 64 49 characters

s=0
for c in raw_input():s=26*s+ord(c)-64
print s

You can also replace raw_input() with input() to reduce the character count by 4, but that then requires the input to contain quotation marks around it.

And here's a subroutine that clocks in at 47 characters:

f=lambda x:len(x)and 26*f(x[:-1])+ord(x[-1])-64
Adam Rosenfield
-1: Not a full program.
KennyTM
@KennyTM: Fixed
Adam Rosenfield
your #2 should be named f. Try running it now, it doesn't work. And it can be made shorter(47 characters) with the help of lambdas and short circuit evaluation: `f=lambda x:len(x)and 26*f(x[:-1])+ord(x[-1])-64`
Wallacoloo
@wallacoloo: Thanks. It's a community wiki, so you can feel free to make edits any time.
Adam Rosenfield
how about dropping len(x) for x alone? becomes 43 chars: f=lambda x:x and 26*f(x[:-1])+ord(x[-1])-64
Nas Banov
+2  A: 

JavaScript, 93 characters

with(prompt())for(l=length,i=0,v=i--;++i<l;)v+=(charCodeAt(l-1-i)-64)*Math.pow(26,i);alert(v)
JDay
+1 That has to be the worst abuse of the `with` statement I have ever seen. (-:
Na7coldwater
+5  A: 

Ruby 1.9, 21 characters

p'A'.upto(gets).count

Tests:

$ echo -n A| ruby x.rb
1
$ echo -n WTF| ruby x.rb
16074
$ echo -n ROFL| ruby x.rb
326676
S.Mark
The code does not look golfed at all though.
S.Mark
You can use chop instead of strip to gain 1 char
JRL
Thanks @JRL, I was something wrong in usage of `echo A |` , it should be `echo A|`
S.Mark
Use `echo -n` like others and get rid of `chop`.
Daniel
Thanks @Daniel, I have updated it, but looks like `echo -n` is not working on Windows.
S.Mark
+5  A: 
AboutDev
May be they want to use only 64k memory at that time :-)
S.Mark
+1. Ha. You might be right!
AboutDev
Because they wanted to be able to do offsets (x-y) which requires a sign bit. But that's only 15bits, so what's up with the 16th bit? Is it used as a flag?
phkahler
This is not *exactly* base-26, because it has no 0. If we let A represent 1, and multiply with `26^n` for position `n` (with `n = 0` for the rightmost letter), it all works out as usual.
Thomas
@phkahler: With 1 bit, you can represent all unsigned integers in the range 0..2^0. Thus, with 16 bits, you can represent 0..2^15. Take away 1 bit for the sign, the maximum value will be 2^14-1 (=16383).
stakx
@phkahler: you don't need a sign bit to represent offsets as long as you don't need a distinguished representation for out-of-bounds values (i.e. you can check the processor overflow bit to see if you're out of bounds).
Kragen Javier Sitaker
@stakx: Nice trick... But 1 bit can represent 0..2^**1**-1. 16 bits is 0..2^**16**-1. Take away 1 bit for the sign, the maximum value will be 2^**15**-1 (=32767). If you don't believe me, try it with 2 bits. 2 bits is not 0..2^1 = 0..2. You have 00, 01, 10, 11 = 0, 1, 2, 3 in base10 respectively.
Wallacoloo
@wallacoloo: Oops. You're right of course; what was I thinking!
stakx
+4  A: 

in VBA I got it down to 98

Sub G(s)
Dim i, t
For i = 0 To Len(s) - 1
    t = t + ((Asc(Left(Right(s, i + 1), 1)) - 64)) * ((26 ^ i))
Next
MsgBox t
End Sub
Kevin Ross
Surely you don't need the indentation.
Kinopiko
Force of habbit sorry!
Kevin Ross
You don't need to declare the sub as Public, and nor do you need to say "Next i" (just use "Next"). Also, I think if you loop from 1 rather than zero you can shave off a character or two.
Gary McGill
@Gary, thanks for the tips, this is my first "round" of code golf I'm sure I will get better after a few more goes
Kevin Ross
+6  A: 

Powershell, 42 chars

[char[]]$args[($s=0)]|%{$s=$s*26+$_-64};$s
Danko Durbić
+319  A: 

Excel, 9 chars :)

Use the right tool for the job:

=COLUMN()

=COLUMN()

Danko Durbić
Use the right language for the job: Portuguese Excel `=COL()`. 6 characters. (See http://dolf.trieschnigg.nl/excel/excel.html )
Debilski
Great! only it does not support `ROFL` though.
S.Mark
I'm torn between accepting this and the Ruby solution (which is the shortest). Excel really isn't a "language" but still, this is pretty clever :). SO community - what do you think?
Vivin Paliath
I think you should accept my 12 character J solution, but I might be biased. :)
David
Ohh right your J solution is 12 chars :) Hmmm
Vivin Paliath
This solution even reproduces the limitations of Excel correctly.
kibibu
I've decided to go with this one even though it's not a true programming language. Mainly because of how clever it is :)
Vivin Paliath
@Vivin: Excel is of course a true programming language. http://www.gamasutra.com/view/feature/3563/microsoft_excel_revolutionary_3d_.php
KennyTM
It doesn't even take a string as input. Doesn't come close to doing what the problem said. It only works if it's in the column that happens to be named after the string in question. Totally not in the spirit of the question.
phkahler
To be fair, Code Golf is *made* for these kinds of smartass answers. So you get a +1 from me.
Reynolds
+1 for the SO column.
Alex
+3  A: 

Ruby, 21 characters

p ('A'..$*[0]).count

Usage:

$ ruby a.rb ABC
731
Jonas Elfström
+11  A: 

Golfscript - 16 chars

[0]\+{31&\26*+}*


$ echo -n WTF | ./golfscript.rb excel.gs
16074
$ echo -n ROFL | ./golfscript.rb excel.gs
326676
gnibbler
+10  A: 

Haskell, 50 51 56 chars

main=interact$show.foldl(\x->(26*x-64+).fromEnum)0

Usage:

~:166$ echo -n "ROFL" | ./a.out
326676
~:167$ echo -n "WTF" | ./a.out
16074
KennyTM
+70  A: 

J, 17 12 10 characters

26#.64-~av

Example:

26#.64-~av  'WTF'
16074

Explanation:

  • J parses from right to left.
  • av returns a list of the ascii indexes of each of the characters in its argument, so for example av'ABC' returns 65 66 67.
  • Then we subtract 64 from each element of that list with the verb 64-~.
  • Then we convert the list to base 26 using the #. verb.
David
+1 J pwns golfscript when it comes to base conversions :)
gnibbler
After reading a few comments about how the Excel solution really doesn't take a string input, I'm going to go with the solution that is the shortest, and actually takes a string input.
Vivin Paliath
Wow a J solution I can actually understand :)
Callum Rogers
J is made for this stuff.
Brandon Pelfrey
@Brandon: J is made for everything, as long as you don't mind spending years learning how to read it.
David
You are my god.
M28
This blows my mind
Maulrus
+2  A: 

Lua, 61 characters

x=0 for c in(...):gfind(".")do x=x*26-64+c:byte()end print(x)
gwell
*blink* *blink*
RCIX
+4  A: 

C#, 148 chars

using System;class P{static void Main(string[]a){var r=0d;int j=0,i=a[0].
Length;while(i-->0)r+=(a[0][i]-64)*Math.Pow(26,j++);Console.WriteLine(r);}}

Ungolfed:

using System;
class P
{
    static void Main(string[] a)
    {
        var r = 0d;
        int j = 0, i = a[0].Length;
        while (i-- > 0)
            r += (a[0][i] - 64) * Math.Pow(26, j++);

        Console.WriteLine(r);
    }
}
Charles
This one is actually readable.
Robert Harvey
+48  A: 

Brainf*ck, 81 characters (no whitespace)

,[>>>[->>+++++[-<+++++>]<+<]>[-<+>]<<++++++++[<++++++++>-]<[<->-]<[>>>+<<<-],]>>>

Explanation

,[  // get character input into p[0], enter loop if it isn't null (0)
>>>[->>+++++[-<+++++>]<+<] // take what's in p[3] and multiply by 26, storing it in p[4]
>[-<+>] // copy p[4] back to p[3]
<<++++++++[<++++++++>-]< // store 64 in p[1]
[<->-]< // subtract p[1], which is 64, from the input char to get it's alphabetical index
[>>>+<<<-] // add p[0] to p[3]
,] // get another character and repeat
>>> // move to p[3], where our final result is stored

So you'll notice I didn't actually convert the numerical value to an ascii string for printing. That would likely ruin the fun. But I did the favor of moving the pointer to the cell with the result, so at least it's useful to the machine.

Hey, what do you know, I beat C#!

Tesserex
+1 for writing a non-trivial program in Brainf*ck
Dinah
LOL @ Beating C#
Dan
I'm surprised that anyone actually uses Bf in first place
OscarRyz
C'mon man, don't stop there, do the rest of Excel too.
intuited
+1 for converting to BrainF#ck
Anonymous Type
+5  A: 

Common Lisp, 103 128 characters

(defun x(s)(reduce(lambda(x y)(+(* 26 x)y))(map 'vector(lambda(b)(-(char-code b)(char-code #\A)-1))s)))
Paul Richter
+1 to you for using LISP! Awesome!
AboutDev
+21  A: 

APL

13 characters

Put the value in x:

x←'WTF'

then compute it with:

26⊥(⎕aV⍳x)-65

The only reason J beat me is because of the parentheses. I'm thinking there should be some way to rearrange it to avoid the need for them, but it's been a long day. Ideas?

(Heh, you perl programmers with your 30+ character solutions are so cute!)

Ken
Maybe 26⊥⁻65+⎕aV⍳x instead? That is how you write negative 65 in APL, right?
Kragen Javier Sitaker
I don't have my APL environment in front of me right now, but I think I tried something like that and it didn't work. Off the top of my head (and admittedly I'm the furthest thing from an APL wizard!) ⁻ is equivalent to - and since it evaluates right-to-left it's applied after the +, so you end up with 26⊥⁻(65+(⎕aV⍳x)) instead of 26⊥((⁻65)+⎕aV⍳x), which is what you need here.
Ken
Accepted Perl solution beats your code by two characters... =)
kolistivra
+1  A: 

dc - 20 chars

(does the opposite)

dc can't handle character input, so I coded the opposite: input the column number and output the column name:

?[26~64+rd0<LP]dsLxP
dc exccol.dc
326676
 ROFL
Carlos Gutiérrez
dc can handle character input, just set your base to something like 36 with `36i`.
Adam Rosenfield
@Adam - It doesn't work (at least on the GNU version) 36i dc: input base must be a number between 2 and 16 (inclusive)
Carlos Gutiérrez
A: 

how about a new language
with operators defined as

# - will return the =COLUMN() of EXCEL as a stringised number

, - read in a string

. - write out a string

then the program to do that is

,#.

alvin
I hope future code golfs create a rule saying **The language must be Turing complete** to stop these rotten jokes.
KennyTM
Simple. Define an extension of HQ9+B (which itself is a Turing-complete extension of HQ9+) that has three new operators...
Jouni K. Seppänen
The actual solution is to get chip manufacturers to implement a machine instruction for these problems.
Jonno_FTW
@Kenny: just another perspective in the spirit of ioccc :)http://en.wikipedia.org/wiki/International_Obfuscated_C_Code_Contest#Rules
alvin
even each package/library used implies a meta-linguistic abstraction.so if i wrote a package to solve this problem with one api call, and accidentally that package got included into the standard library :) of any one the turing complete languages, i would be able to solve the problem in just one api call. will it then be counted as a valid answer. so atleast the language should be constrained to the plain base language, without using any libraries.some of the answers use the math or the string libraries. should'nt the source code size of those calls be counted in too?
alvin
This won't work, due to Excel's column count limitations. In fact this problem cannot be solved in your new language.
intuited
@intuited. that is interesting.
alvin
@alvin: now if you add in a function to convert veganhexisimula [sp!] into decimal, well then you're rockin. But it's still making up the rules as you go, and the rules are "I win."
intuited
+3  A: 

PHP - 73 Chars

$n=$argv[1];$s=$i=0;while($i<strlen($n))$s=$s*26+ord($n[$i++])-64;echo$s;

Usage:

php -r '$n=$argv[1];$s=$i=0;while($i<strlen($n))$s=$s*26+ord($n[$i++])-64;echo$s;' AA

> 27
Kevin
You could lose 10 characters by removing the curly braces around your while function and dumping the variable initialization.
ChiperSoft
+2  A: 

Java: 112 124 characters

class C{public static void main(String[]a){int r=0;for(int b:a[0].getBytes())r=26*r+b-64;System.out.print(r);}}
Robin
+1  A: 

My Javascript solution is just 82 characters long and uses Integer.parseInt with Radix 36. It'd be fine if somebody could appen this to the Javascript section of this thread! :-)

a=function(b){t=0;b.split('').map(function(n){t=parseInt(n,36)-9+t*26});return t};
beNi
+1  A: 

PHP:

<?$t=0;$s=str_split($argv[1]);$z=count($s);foreach($s as$v){$z--;$t+=(ord($v)-64)*pow(26,$z);}echo$t?>

usage: php filename.php ROFL

outputs: 326676

omgooses
+5  A: 

C#, 117 111 chars

No contest compared to the likes of Perl, Ruby and APL but an improvement on the other C#/Java answers given so far.

This uses Horner's rule.

class C{static void Main(string[]a){int t=0;foreach(var c in a[0]){t=(t+c-64)*26;}System.Console.Write(t/26);}}
Daniel Renshaw
You can save 3 chars by removing the space between the [] and the 'a', and the foreach braces.
Cameron MacFarland
I didn't know string implemented IEnumerable. Sweet! Unfortunately the page about Horner's rule is way over my head, but clearly a winning strategy. I don't like using Console.Write() though, due to the messy output. +1
Charles
+2  A: 

wazoox:

echo -n WTF | perl -ple '$=()=A..$'

This prints a new line so the answer is more readable on the shell.

+4  A: 

Python - 63 chars

>>> f=lambda z: reduce(lambda x,y: 26*x+y, [ord(c)-64 for c in z])

>>> f('ROFL')

326676

sleeper
+4  A: 

Common Lisp, 86 characters.

(defun z(s)(let((a 0))(map nil(lambda(v)(setf a(+(* 26 a)(digit-char-p v 36)-9)))s)a))
Zhivago
+4  A: 

Clojure:

user> (reduce #(+ (* 26 %1) %2) (map #(- (int %) 64) "AD"))
30
user> (reduce #(+ (* 26 %1) %2) (map #(- (int %) 64) "ROFL"))
326676

51 characters, plus the number of characters in the input string.

jimbokun
+2  A: 

Smalltalk, 72

Smalltalk arguments first reverse inject:0into:[:o :e|o*26+e digitValue]
Paolo Bonzini
For a moment I thought you'd written an implementation of Smalltalk-72 for this, then I realized the "72" was the number of characters.
Kragen Javier Sitaker
+6  A: 

Scala, 30 chars

print((0/:args(0))(_*26+_-64))" 

Example:

C:\>scala -e "print((0/:args(0))(_*26+_-64))" AD
30
Daniel
+2  A: 

PHP: 56 55 characters

for($i='a';$i++!=strtolower($argv[1]);@$c++){}echo++$c;

PHP: 44 43 characters only for uppercase letters

for($i='A';$i++!=$argv[1];@$c++){}echo++$c;

chebur
+9  A: 

Excel (not cheating), 25 chars

Supports up to XFD:

=COLUMN(INDIRECT(A1&"1"))

Installation:

  1. Put the formula in cell A2.

Usage:

  1. Enter the column string in cell A1.
  2. Read the result at cell A2.

54 chars, plus a lot of instructions

Supports ROFL also:

(A2)  =MAX(B:B)
(B2)  =IFERROR(26*B1+CODE(MID(A$1,ROW()-1,1))-64,0)

Installation:

  1. Clear the whole spreadsheet.
  2. Put the formula (A2) in cell A2.
  3. Put the formula (B2) in cell B2.
  4. Fill formula (B2) to as far down as possible.

Usage:

  1. Enter the column string in cell A1.
  2. Read the result at cell A2.
KennyTM
+2  A: 

Applescript: 188
Here's the requisite applescript in 188 characters, which is a very difficult language to make non-verbose. It also happens to be the longest answer of any language so far. If anyone knows how to shorten it, do share.

on run s  
 set {o, c} to {0, 0}  
 repeat with i in reverse of (s's item 1)'s characters  
  set m to 26 ^ c as integer  
  set c to c + 1  
  set o to o + ((ASCII number of i) - 64) * m  
 end repeat  
end run

Usage:
osascript /path/to/script.scpt ROFL

cyno
+1  A: 

Python (47 chars)

reduce(lambda a,b:a*26+ord(b)-64,raw_input(),0)

works only on uppercase letters

amashi
+3  A: 

Common Lisp, 81 characters

(defun y(s)(reduce(lambda(x y)(+(* 26 x)(-(char-code y)64)))s :initial-value 0))

Funny that as a new user I can post my own answer but not comment on someone else's. Oh well, apologies if I'm doing this wrong!

I think you will have to register :) Then you'll be able to comment.
Vivin Paliath
+3  A: 

C:

int r=0;
while(*c)r=r*26+*c++-64;

String is stored in 'c', value is in 'r'.

fluffy
+5  A: 

k4 (kdb+), 11 characters

26/:1+.Q.A?

Explanation:

  • k4 parses left of right
  • .Q.A is defined within k4 - it is the vector "ABC...XYZ"
  • ? is the find operator - the index of the first match for items in the y arg within the x arg
  • +1 to offset the index
  • 26/: to convert to base 26

One caveat - this will only work where listed types are passed in:

  26/:1+.Q.A? "AD"
30

  26/:1+.Q.A? "WTF"
16074

but:

  26/:1+.Q.A? ,"A"
1
Ciarán
A: 

Real VBA, 216 w/o spaces

I fail at real golf too.

Private Sub CB1_Click()
Dim C, S
Range("A1").Select
Do
S = Len(ActiveCell)
x = 0
C = 0
Do
C = (Asc(Mid(ActiveCell, (S - x), 1)) - 64) * (26 ^ x) + C
x = x + 1
Loop Until x = S
ActiveCell.Offset(0, 1) = C
ActiveCell.Offset(1, 0).Activate
Loop Until ActiveCell = ""
End Sub

Uses Column A for input, outputs to Column B, runs off a VB command button click. =D

Drew
A: 

Elang, 53/78

Shell, 53 characters:

F=fun(S)->lists:foldl(fun(C,A)->A*26+C-64end,0,S)end.

Module, 78 characters:

-module(g).
-export([f/1]).
f(S)->lists:foldl(fun(C,A)->A*26+C-64end,0,S).
Philip Robinson
A: 

F# 92 chars :)


let e2n (c : string) = c |> Seq.map (fun x -> (int)x - 64) |> Seq.reduce(fun e a -> a*26+e)

Johnny El Men
+2  A: 

PHP, 38 chars

for($a=A;++$c,$a++!=$argv[1];);echo$c;

usage, e.g.

php -r 'for($a=A;++$c,$a++!=$argv[1];);echo$c;' WTF
rebel
+1  A: 

Matlab 38 chars


Works only with uppercase letters. Not sure if it has to work with lowercase too (none in example).

x=input('')'-64;26.^(size(x)-1:-1:0)*x

If new lines do not count only 37 (omitting semicolon):

x=input('')'-64
26.^(size(x)-1:-1:0)*x

I see Matlab beats a lot of languages. Who would expect that.

Example:

Input: 'ROFL' (dont forget the '' )
Output: ans = 326676
George B.
+1  A: 

Factor: 47 characters

reverse [ 26 swap ^ swap 64 - * ] map-index sum

Hugo Schmitt
A: 

Excel - 99 characters

Enter as array formula - I am not counting Excel adding { }

=SUM((CODE(MID(A1,ROW(INDIRECT("1:" & LEN(A1))),1))-64)*26^(LEN(A1)-ROW(INDIRECT("1:" & LEN(A1)))))

RonnieDickson
A: 

Groovy: 51 Characters

char[] a=args[0];t=0;for(i in a)t=26*t+i-64;print t

Invoke as

groovy *scriptname* ROFL

or

groovy -e "char[] a=args[0];t=0;for(i in a)t=26*t+i-64;print t" ROFL

This essentially the same as Java. I imagine some possibilities with using ranges and closures, but nothing came to mind for this example. Anyone else see a way to shorten this?

A more groovy-looking version with a closure is a bit longer, unfortunately.

t=0;args[0].toCharArray().each{t=t*26+it-64};print t
DaveG
+2  A: 

MATLAB: 24 characters

polyval(input('')-64,26)

Usage:

>> polyval(input('')-64,26)
(after pressing enter) 'WTF'

ans =

       16074

Note: You can get it down to 16 characters if you pre-store the string in x, but I kind of thought it was cheating:

>> x = 'WTF'

x =

WTF

>> polyval(x-64,26)

ans =

       16074
rlbond
How could I forget about polyval.. +1 for better solution
George B.
A: 

Go: 106 characters

It's not the shortest of all the languages. But it can be the shortest of C, C++, Java, and C#.

package main
import("os"
"fmt")
func main(){t:=0
for _,c := range os.Args[1]{t=t*26+c-64}
fmt.Println(t)}

Formated version:

package main

import (
    "os"
    "fmt"
)

func main() {
    t := 0
    for _, c := range os.Args[1] {
        t = t*26 + c - 64
    }   
    fmt.Println(t)
}
Stephen Hsu
+1  A: 

Prolog: 49 chars

c([],A,A).
c([H|T],I,R):-J is H-64+I*26,c(T,J,R).

Using the above code:

| ?- c("WTF",0,R).
R = 16074 ? 
yes
| ?- c("ROFL",0,R).
R = 326676 ? 
yes
Michael
+1  A: 
elias
A: 

Python: 88 characters

using list comprehensions:

s=input()
print sum([((26**(len(s)-i-1))*(ord(s[i])-64)) for i in range(len(s))])
thepandaatemyface
A: 

Josl in 48 characters

main 0 0 argv each 64 - swap 26 * + next print

Examples:

$ josl numequiv.j A
1
$ josl numequiv.j ABC
731
$ josl numequiv.j ROFL
326676

Reading from standard input:

main 0 STDIN read-line each 64 - swap 26 * + next print
jeremy
+1  A: 

OOBasic: 178 characters, not counting indentational whitespace

revised

This version passes all the test cases. I suspect that it would be more successfully golf if it didn't "take advantage" of the fact that there's a spreadsheet using this numbering system. See the notes on the original version below for info on why that's not particularly useful. I didn't try very hard to cut down the score.

Also note that this will only work when run as a macro from an OO calc spreadsheet, for obvious reasons.

Function C(st as String) as Long
    C = 0
    while len(st)
        C = C*26 + ThisComponent.Sheets(0).getCellRangeByName(left(st,1) &"1").CellAddress.Column+1
        st = mid(st,2)
    wend
End Function

original

OOBasic (OpenOffice Basic), too many characters (124):

Function C(co As String) As Long 
    C = ThisComponent.Sheets(0).getCellRangeByName(co &"1").CellAddress.Column+1
End Function

Limitations:

  • maximum value of co is AMJ (1024 columns). Anything larger results in an error with a completely uninformative error message.
    • This limitation is also present for the COLUMN() cell function. Presumably this is the maximum number of columns in an OOCalc spreadsheet; I didn't bother scrolling over that far or googling to find out.

Notes:

  • strangely it's not possible to give the variable 'co' a 1-letter name. Not sure what the logic is behind this, but after having spent enough time using OOBasic you stop looking for logic and begin to blindly accept the way things are (perhaps from gazing too long at the Sun).

Anyway entering =C("A"), =C("ABC"), etc. in a cell works for the first four test cases; the last two give errors.

intuited
A: 

straight bash

filter: 97 chars

{ read c;i=0;while [ $c ];do eval s=({A..${c:0:1}});i=$((i*26+${#s[@]}));c=${c:1};done;echo $i;}

Usage:

echo ROFL | { read c;i=0;while [ $c ];do eval s=({A..${c:0:1}});i=$((i*26+${#s[@]}));c=${c:1};done;echo $i;}
326676

function: 98 chars

C(){ i=0;while [ $1 ];do eval s=({A..${1:0:1}});i=$((i*26+${#s[@]}));set -- ${1:1};done;echo $i;}

Usage:

C ROFL
326676

Explanation of the filter version:

read c;i=0;

Initialize the column and the total.

while [ $c ];do

while there are still column characters left

eval s=({A..${c:0:1}});

${c:0:1} returns the first character of the column; s=({A..Z}) makes s an array containing the letters from A to Z

i=$((i*26+${#s[@]}));

$((...)) wraps an arithmetic evaluation; ${#s[@]} is the number of elements in the array $s

c=${c:1};done;

${c:1} is the characters in $c after the first. done ends the while loop

echo $i

um i forget

better but dubious

Removing the 5 characters "echo " will result in the output for an input of "ROFL" being

326676: command not found

Also the i=0 is probably not necessary if you're sure that you don't have that variable set in your current shell.

intuited
+1  A: 

F# (37 chars):

Seq.fold (fun n c -> int c-64+26*n) 0
Jon Harrop
A: 

K 3.2 (13 characters)

26_sv -64+_ic

Usage:

  26_sv -64+_ic"ROFL"
326676

Explanation:

  • As mentioned above K evaluates from right to left, so the _ic function takes whatever is to its right and converts it to an integer value, this includes both single characters and character vectors
  • -64 is added to each item in the integer vector that to get a set of base values
  • _sv takes two arguments: the one on its left is the numeric base, 26, and the one on its right is the integer vector of offset values
afshin
+1  A: 

Excel VBA, 19 characters:

range("WTF").Column

iDevlop
A: 

Ruby solution in 26 chars

p ("A"..$*[0]).to_a.size

Gerhard