Code Golf: Numeric equivalent of an Excel column name
ExcelCode GolfExcel Problem Overview
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).
Excel Solutions
Solution 1 - Excel
Excel, 9 chars :)
Use the right tool for the job:
=COLUMN()
Solution 2 - Excel
36 34 33 31 30 17 15 11 characters
Perl, $_=()=A..$_
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>; $scalar = @list
.
Solution 3 - Excel
J, 17 12 10 characters
26#.64-~av
Example:
26#.64-~av 'WTF'
16074
Explanation:
-
J parses from right to left.
-
av
returns a list of the ascii indexes of each of the characters in its argument, so for exampleav'ABC'
returns65 66 67
. -
Then we subtract 64 from each element of that list with the verb
64-~
. -
Then we convert the list to base 26 using the
#.
verb.
Solution 4 - Excel
Brainf*ck, 81 characters (no whitespace)
,[>>>[->>+++++[-<+++++>]<+<]>[-<+>]<<++++++++[<++++++++>-]<[<->-]<[>>>+<<<-],]>>>
Explanation
,[ // get character input into p[0], enter loop if it isn't null (0)
>>>[->>+++++[-<+++++>]<+<] // take what's in p[3] and multiply by 26, storing it in p[4]
>[-<+>] // copy p[4] back to p[3]
<<++++++++[<++++++++>-]< // store 64 in p[1]
[<->-]< // subtract p[1], which is 64, from the input char to get it's alphabetical index
[>>>+<<<-] // add p[0] to p[3]
,] // get another character and repeat
>>> // move to p[3], where our final result is stored
So you'll notice I didn't actually convert the numerical value to an ascii string for printing. That would likely ruin the fun. But I did the favor of moving the pointer to the cell with the result, so at least it's useful to the machine.
Hey, what do you know, I beat C#!
Solution 5 - Excel
53 50 46 44 24 17 characters
Ruby 1.8.7, p ('A'..$_).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
Solution 6 - Excel
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!)
Solution 7 - Excel
Excel (not cheating), 25 chars
Supports up to XFD:
=COLUMN(INDIRECT(A1&"1"))
Installation:
- Put the formula in cell A2.
Usage:
- Enter the column string in cell A1.
- 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:
- Clear the whole spreadsheet.
- Put the formula (A2) in cell A2.
- Put the formula (B2) in cell B2.
- Fill formula (B2) to as far down as possible.
Usage:
- Enter the column string in cell A1.
- Read the result at cell A2.
Solution 8 - Excel
156 146 118 Chars
C# 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);
}
}
Solution 9 - Excel
Golfscript - 16 chars
[0]\+{31&\26*+}*
$ echo -n WTF | ./golfscript.rb excel.gs
16074
$ echo -n ROFL | ./golfscript.rb excel.gs
326676
Solution 10 - Excel
51 56 chars
Haskell, 50 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
Solution 11 - Excel
64 49 characters
Python, 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
Solution 12 - Excel
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
Solution 13 - Excel
JavaScript 1.8: 66 characters
function a(p)Array.reduce(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
Solution 14 - Excel
Powershell, 42 chars
[char[]]$args[($s=0)]|%{$s=$s*26+$_-64};$s
Solution 15 - Excel
Scala, 30 chars
print((0/:args(0))(_*26+_-64))"
Example:
C:\>scala -e "print((0/:args(0))(_*26+_-64))" AD
30
Solution 16 - Excel
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.
Solution 17 - Excel
Explanation of Concepts - Excelcification
Nice. I wrote my own version of this with a little more explanation a long time ago at http://aboutdev.wordpress.com/2009/12/19/excelcification-brain-teaser-code/. Although it's not quite an optimized version!
FYI. The base 26 arithmetic is called hexavigesimal and Excel's maximum column is XFD which converts to 16383 (using 0 as the first cell) which is coincidentally exactly 2^14 cells.
Can anyone guess as to why it is 2^14??
Solution 18 - Excel
128 characters
Common Lisp, 103 (defun x(s)(reduce(lambda(x y)(+(* 26 x)y))(map 'vector(lambda(b)(-(char-code b)(char-code #\A)-1))s)))
Solution 19 - Excel
117 111 chars
C#, 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);}}
Solution 20 - Excel
Perl, 34 characters
map$\=26*$\-64+ord,pop=~/./g;print
Thanks to mobrule for several suggestions.
Solution 21 - Excel
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
Solution 22 - Excel
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);
}
}
Solution 23 - Excel
Python - 63 chars
> >>> f=lambda z: reduce(lambda x,y: 26*x+y, [ord(c)-64 for c in z]) > > >>> f('ROFL') > > 326676
Solution 24 - Excel
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))
Solution 25 - Excel
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.
Solution 26 - Excel
C:
int r=0;
while(*c)r=r*26+*c++-64;
String is stored in 'c', value is in 'r'.
Solution 27 - Excel
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
Solution 28 - Excel
Ruby, 20 characters
p('A'..$*[0]).count
Usage:
$ ruby a.rb ABC
731
Solution 29 - Excel
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
Solution 30 - Excel
124 characters
Java: 112 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);}}
Solution 31 - Excel
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!
Solution 32 - Excel
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
Solution 33 - Excel
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:
vivin@serenity ~/Projects/code/perl/excelc
$ echo WTF | perl e.pl
16074
vivin@serenity ~/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.
Solution 34 - Excel
Perl, 47 characters (from stdin)
chop($l=<>);$_=A;$.++,$_++while$_ ne$l;die$.,$/
Solution 35 - Excel
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)
Solution 36 - Excel
Lua, 61 characters
x=0 for c in(...):gfind(".")do x=x*26-64+c:byte()end print(x)
Solution 37 - Excel
wazoox:
echo -n WTF | perl -ple '$=()=A..$'
This prints a new line so the answer is more readable on the shell.
Solution 38 - Excel
Smalltalk, 72
Smalltalk arguments first reverse inject:0into:[:o :e|o*26+e digitValue]
Solution 39 - Excel
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;
Solution 40 - Excel
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 sUsage:
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
osascript /path/to/script.scpt ROFL
Solution 41 - Excel
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
Solution 42 - Excel
APL: 7 characters
Store desired string in variable w:
w←'rofl'
Assuming characters are lowercase:
26⊥⎕a⍳w
Assuming characters are uppercase:
26⊥⎕A⍳w
Mixed case or unsure of case (14 chars, but could possibly be improved):
26⊥⊃⌊/⎕a⎕A⍳¨⊂w
Solution 43 - Excel
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
Solution 44 - Excel
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.
Solution 45 - Excel
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
Solution 46 - Excel
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};
Solution 47 - Excel
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
Solution 48 - Excel
Python (47 chars)
reduce(lambda a,b:a*26+ord(b)-64,raw_input(),0)
works only on uppercase letters
Solution 49 - Excel
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
Solution 50 - Excel
Factor: 47 characters
reverse [ 26 swap ^ swap 64 - * ] map-index sum
Solution 51 - Excel
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
Solution 52 - Excel
php 29 chars:
while($i++!=$t)$c++;echo$c+1;
- assuming register_globals=On
- assuming error_reporting=0
- call via webserver ?i=A&t=ABC
Solution 53 - Excel
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))])
Solution 54 - Excel
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
Solution 55 - Excel
OOBasic: 178 characters, not counting indentational whitespace
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. revised
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.
Solution 56 - Excel
filter: 97 chars straight bash
{ 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 $i
um i forget
better but dubious
Removing the 5 characters "echo " will result in the output for an input of "ROFL" being
326676: command not found
Also the i=0
is probably not necessary if you're sure that you don't have that variable set in your current shell.
Solution 57 - Excel
F# (37 chars):
Seq.fold (fun n c -> int c-64+26*n) 0
Solution 58 - Excel
K 3.2 (13 characters)
26_sv -64+_ic
Usage:
26_sv -64+_ic"ROFL"
326676
Explanation:
- As mentioned above K evaluates from right to left, so the _ic function takes whatever is to its right and converts it to an integer value, this includes both single characters and character vectors
- -64 is added to each item in the integer vector that to get a set of base values
- _sv takes two arguments: the one on its left is the numeric base, 26, and the one on its right is the integer vector of offset values
Solution 59 - Excel
Excel VBA, 19 characters:
range("WTF").Column
Solution 60 - Excel
Ruby solution in 26 chars
p ("A"..$*[0]).to_a.size
Solution 61 - Excel
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
Solution 62 - Excel
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).
Solution 63 - Excel
F# 92 chars :)
let e2n (c : string) = c |> Seq.map (fun x -> (int)x - 64) |> Seq.reduce(fun e a -> a*26+e)
Solution 64 - Excel
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
Solution 65 - Excel
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)
}
Solution 66 - Excel
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)))))
Solution 67 - Excel
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
,#.