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Question

Given a string as input, output a number of whitespace characters (0x0A and 0x20) equal to the length of the string.

For example, given the string Hello, World! your code would need to output exactly 13 whitespace characters and nothing else. These can be any mix of spaces and newlines.

Your code should not output any additional trailing newlines or spaces.

Testcases:

 Input -> Amount of whitespace to output
"Hello, World!" -> 13
"Hi" -> 2
" Don't
Forget about
Existing
Whitespace! " -> 45
"" -> 0
" " -> 13
"
" -> 1

Scoring:

This is code-golf so fewest bytes wins!

• manatwork: I don't get what you mean with that "0x0A". Where should that be output? Should that be kept, so "a␠b␊c" becomes "␠␠␠␊␠"?
• Mayube: @manatwork 0x0A and 0x20 are the hexadecimal values for the Newline and Space characters respectively
• manatwork: "output a number of whitespace characters (0x0A and 0x20)" – Where in the output should those newline characters be?
• Mayube: These can be any mix of spaces and newlines Your output can be any mix of spaces and newlines, you can just output spaces if you want, like everyone else, or you can just output newlines. It's up to you
• Luis Mendo: Can we assume the input will only have printable characters?

Answer 1

Cubix, 6 bytes

Wahoo a 6 byter!

wi?@oS

Cubified

 w
i ? @ o
 S

• i gets input
• ? test top of stack
  • if negative (EOI) redirect onto w lane change which umps to the @ halt
  • if 0 (null) halt this shouldn't be hit
  • if positive Sow push space to the stack, output and change lane onto i

Try it online!

• ETHproductions: Sweet, it's not too often a Cubix program is this short :-)

Answer 2

C, 32 bytes

Try Online modifying characters into spaces

f(char*t){(*t=*t?32:0)&&f(t+1);}

C, 37 bytes

Try Online Left-padding the end-of-string with its length

f(char*t){printf("%*c",strlen(t),0);}

• l4m2: 29

Answer 3

APL (Dyalog) 13.2, 1 byte

Prints only spaces.

∊ prototype (numbers become zeros, characters become spaces)

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Answer 4

Pepe, (削除) 46 (削除ここまで) 37 bytes

REEeRREeeeREEEEErEeeEeeeeerEEeeeEreee

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Explanation:

REEe # Input (string) in R
RREeee # Push reverse pointer position, or length of input - 1
 # R flag: push in beginning
REEEEE # ...add 1
rEeeEeeeee # Push space in r
rEEeeeE # ...R times
reee # Output whole stack

Answer 5

Poetic, 81 bytes

the berenstein bears
i remember a series i spelled wrong
o m gee,i do remember it

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The misspelling is intentional. (...or is it?)

Answer 6

Gema, 4 characters

?=\ 

(There is a space at the end of code.)

Sample run:

bash-4.4$ echo -n 'Hello, World!' | gema '?=\ '
 bash-4.4$ echo -n 'Hello, World!' | gema '?=\ ' | wc
 0 0 13

Answer 7

APL (Dyalog), 3 bytes

Prints only newlines.

0/⍪

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⍪ table (makes string into column matrix)

0/ replicate each column zero times

Answer 8

Scala, 15 bytes

s=>" "*s.length

• jrook: I created a Try it online for your program.

Answer 9

JavaScript (ES8), 22 bytes

s=>"".padEnd(s.length)

Answer 10

Java 8, 24 bytes

s->s.replaceAll("."," ")

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Java 7, 49 bytes

String c(String s){return s.replaceAll("."," ");}

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Answer 11

Chip, 2 bytes

*f

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Chip reads in a byte, does whatever calculations are in the code, and writes a byte. So, for each byte of input, we ignore the input and write 0x20 instead. The empty Chip program would replace each byte of input with a null byte of output.

* Source element, activates any neighbor elements
 f Output element for the bit 0x20, when active this bit is set in the output

Transposing the two characters would result in the same thing. I opted to use spaces, since 0x20 requires only one bit to be set. 0x0a requires setting two bits. Code for that could be:

b*d

Answer 12

Shell utils, (削除) 14 (削除ここまで) 12 bytes

tr ' -~' ' '

tr translates characters in the first parameter, into the corresponding one in the second parameter. (space)-~ is a range for space (32) to tilda (126), the first and last printable ASCII characters. They are mapped into a space; tr duplicates the last character in the output list if it is shorter than the input list.

• RJHunter: You could shave off a couple of bytes with different quoting styles (\ -~ instead of ' -~') and you could even get away without quoting the first parameter at all if you use a control-character byte.
• L3viathan: That brings it down to 9 bytes: tr ␁-~ \ (␁=^A)

Answer 13

shortC, 16 bytes

f(C*a){W*a++)P' 

Note the trailing space at end of code.

Conversions in this program:

• C -> char
• W -> while(
• P -> putchar(

The resulting program looks like this:

f(char *a){while(*a++)putchar(' ');}

How that works:

• while(*a++) loops until it reaches the last index of the string a.
• putchar(' '); prints a space for each index of a.

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Answer 14

dc, (削除) 25 (削除ここまで) 18 bytes

-1 byte thanks to brhfl

Z[1-d0<L32P]sLd0<L

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Explanation:

Z[1-d0<L32P]sLd0<L
 Implicit input
Z Get length
 [ ]sL Create a funcion and saves in L
 d0<L If length > 0, call L
 1- Subtract 1 from the length
 d0<L If length > 0, call L
 32P Print space

• Maya: Woah! It's worse than German. It would be neat if you explained how it works ;)
• Felipe Nardi Batista: @NieDzejkob there :D
• brhfl: @Felipe You can shave off one byte by using the ASCII code point for a space instead of a string containing a space: 32P instead of [ ]P. I doubt it can be golfed down much further...
• Felipe Nardi Batista: @brhfl didn't know i could do that, thanks

Answer 15

Ruby -p, 10 bytes

$_=$/*~/$/

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Explanation:

$_= Output equals
 $/ the output separator (defaults to newline)
 * repeated a number of times equal to
 ~ the index in the input of the first match of
 /$/ the regular expression for "end of line"

Answer 16

Powershell, (削除) 18 (削除ここまで) 12 bytes

-6 bytes thanks @Julian

$args|%{' '}

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Testscript (use LF only mode in your editor):

$f = {
$args|% t*y|%{' '}
}
@(
,(13, "Hello, World!")
,(2, "Hi")
,(45, " Don't
Forget about
Existing
Whitespace! ")
,(0, "")
,(13, " ")
,(1,"
")
) | % {
 $len,$source=$_
 $r = &$f $source
 $l=$r.length
 "$($l-eq$len): $l"
}

Output:

True: 13
True: 2
True: 45
True: 0
True: 13
True: 1

Powershell + Regex, 20 bytes

$args-replace'.',' '

• Julian: You can go down 6 bytes using splatting ? Try it online!
• mazzy: Thanks. Three years ago we didn't use splatting. Thanks again.

Answer 17

Trilangle, 11 bytes

i7#'@"o.:2L

Unfolds to this:

 i
 7 #
 ' @ "
 o . : 2
L . . . .

This has to be the most creative way I've used @ yet: when hit in one direction, it ends the program; when hit in a different direction, it's divided by 2 to get a space.

Roughly equivalent to this C code:

#include <stdio.h>
int main() {
 while (getchar() != EOF) {
 printf(" ");
 }
}

Answer 18

☾, 4 chars

code

⨝○しろまる󷺼s

A simple test is here.

Explanation

explanation

Answer 19

Perl 6, 10 bytes

{S:g/./ /}

Basic string substitution.

Answer 20

Convex, 2 bytes

,*

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Simply takes the length of the input and multiplies by newlines (which are at the bottom of the stack)

Answer 21

Bash, 16 bytes

printf %*s ${#1}

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Uses parameter expansion count the length of the argument ${#1}, and then printf to output an empty string space-padded to that same length.

• набиячлэвэлиь: printf %${#1}s is 14 bytes; tr -c '' \ (with input from the standard input stream) is 11

Answer 22

PowerShell, 21 bytes

[char[]]"$args"|%{""}

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prints newlines.

• briantist: .....I like it!
• colsw: @briantist thanks for the TIO link, need to get into the habit of doing them myself.
• briantist: can't go wrong, it creates the whole post for you. That's why I use it even when the code itself can't run in TIO 😂

Answer 23

APL, (削除) 11 (削除ここまで) 6 bytes

5 bytes saved thanks to @Adám

' '⍴⍨≢

Uses the Dyalog Classical character set.

• Adám: You can golf this significantly. First, swap the arguments of rho to remove the parentheses: {' '⍴⍨⍴,⍵}, then use tally rather than rho to remove the comma: {' '⍴⍨≢⍵}, and finally, make it into a train to remove the braces and omega: ' '⍴⍨≢.
• Adám: No problem. I'll be happy to teach you more over in the APL chat room.
• Erik the Outgolfer: How is this 5 bytes?
• Uriel: @EriktheOutgolfer fixed, thanks. it counts 6 with the Dyalog char set
• Adám: Save another byte by removing the space.

Answer 24

Perl 5, 6 + 1 = 7 bytes

Uses the -p flag.

y// /c

y/// is the transliteration operator: the first list is translated to the corresponding character in the second list. Without the c, this does nothing, but the c complements the first list, so all characters are transliterated to a space.

Answer 25

Aceto, 5 bytes

Trivial in Aceto:

p
,'O

Reads a character, pushes a space, prints it, and goes back to the start.

Answer 26

T-SQL, 32 bytes

SELECT SPACE(LEN(a+'x')-1)FROM t

Microsoft SQL's LEN function ignores trailing spaces, so this hacky workaround is required.

Input is stored in varchar column a in pre-existing table t, per our input rules.

Answer 27

q/kdb+, (削除) 14 (削除ここまで) 9 bytes

Solution:

{" "}each

Example:

q){" "}each"Hello, World"
" "

Explanation:

Returns " " for each character of the input.

Notes:

I've made a shorter version (7 bytes) that does something similar:

{y}'" "

... but you have to prepend the input rather than append:

q)"hello world"{y}'" "
" "

• coltim: Using one of the k's, 2 bytes is possible as "", e.g. this ngn/k version.

Answer 28

TI-Basic, 13 bytes

For(I,2,length(Ans
Disp "
End

Loop starts at 2 because an additional newline is printed before Done at the end of the program.

Answer 29

MATL, (削除) 3 (削除ここまで) 4 bytes

nqZ"

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Today I learnt that MATLAB has a function for creating a string of spaces!

n - count the number of bytes in input string
q - decrement by 1, because the implicit disp at the end adds a newline (so the number of spaces required is string length - 1)
Z" - blanks command: create a string with the specified number of spaces in it
(Implicit output at end, with trailing newline.)

Answer 30

R, (削除) 37 (削除ここまで) 23 bytes

gsub("."," ",scan(,""))

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14 bytes saved by ngm.

• Giuseppe: apart from using gsub, strrep exists as well, so strrep(" ",nchar(scan,""))) would work (even though it's longer than @ngm 's suggestion)
• JayCe: @Giuseppe Is this a recent function? I can't believe I'm hearing about it for the first time.
• Giuseppe: It appears to have been added in 3.3.0. I haven't really found a great use for it; usually the first thing I do when I see a string is to utf8ToInt it and then I can just use rep for mostly the same purpose, and rep has finer control beyond just times, with each, length.out