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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!

I don't get what you mean with that “0x0A”. Where should that be output? Should that be kept, so “a␠b␊c” becomes “␠␠␠␊␠”? — manatwork, May 25 '17 at 12:56
@manatwork 0x0A and 0x20 are the hexadecimal values for the Newline and Space characters respectively — Skidsdev, May 25 '17 at 12:58
“output a number of whitespace characters (0x0A and 0x20)” – Where in the output should those newline characters be? — manatwork, May 25 '17 at 13:00
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 — Skidsdev, May 25 '17 at 13:05

snail_ · Accepted Answer · 2017-05-25 12:59:33Z

1

SmileBASIC 3, 22 bytes

Asks for a string from the console as input, then prints length spaces. PRINT (or ? here) adds a trailing newline by default, so we use the ; to disable it.

LINPUT A$?" "*LEN(A$);

answered May 25 '17 at 12:59

snail_

1,9625 silver badges15 bronze badges

\$\begingroup\$ This technically isn't valid since LINPUT doesn't accept newlines, so you'll have to define a function (also ; isn't required because PRINT doesn't really output newlines) \$\endgroup\$ – 12Me21 Mar 3 '18 at 16:18

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J42161217 · Accepted Answer · 2017-05-25 13:02:48Z

1

Mathematica, 30 bytes

Row@Table[" ",StringLength@#]&

answered May 25 '17 at 13:02

J42161217

15.5k2 gold badges15 silver badges57 bronze badges

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Felipe Nardi Batista · Accepted Answer · 2017-05-25 13:48:14Z

1

Lua, 25 bytes

for i=1,#...do
print()end

Same length as:

io.write((' '):rep(#...))

Try it online!

edited May 25 '17 at 13:48

answered May 25 '17 at 13:32

Felipe Nardi Batista

2,3451 gold badge9 silver badges31 bronze badges

\$\begingroup\$ Test output length here \$\endgroup\$ – Felipe Nardi Batista May 25 '17 at 14:19

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sergiol · Accepted Answer · 2017-05-25 13:53:32Z

tcl, 19

regsub -all . $s \

demo

To test it, click "Run it" button and then select the white space on the white bottom area. A better test is to add a space and a letter before the ] as I describe:

puts [regsub -all . $s \  x]    
                        ^^ Two spaces here

and it will output the count of characters of each string exactly equal to the ones on the question.

TheLethalCoder · Accepted Answer · 2017-05-25 16:08:28Z

1

Rust, 23 bytes

|s|" ".repeat(s.len());

First time using Rust so not 100% sure I've got everything correct, let me know if I need to change anything. I couldn't work out how to test this, as I'm still new to it, but judging from the documentation it should work. Also any improvements are more than welcome!

answered May 25 '17 at 16:08

TheLethalCoder

6,92016 silver badges41 bronze badges

1

\$\begingroup\$ Hi fellow newbie! I tried to rig up enough surrounding code to make a Try It Online link for this answer (and any similar Rust entries). I did get somewhere but I needed to add a type declaration at the cost of an extra 5 bytes (for a total of 28 bytes) to get it to compile. \$\endgroup\$ – RJHunter May 26 '17 at 3:48

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Riley · Accepted Answer · 2017-05-25 19:12:01Z

Brain-Flak, 28 bytes

{{}<>((()()()()()){})<>}<>{}

Try it online!

{{}                    }     # For every input character...
     ((()()()()()){})        #    Push 10...
   <>                <>      #    on the other stack
                        <>   # Switch to the stack with all of the newlines
                          {} # Pop a newline because the interpreter prints a newline :(

undergroundmonorail · Accepted Answer · 2017-05-25 19:26:03Z

1

pb - 17 bytes

^w[B!0]{>}<vb[32]

Goes to the last character of the input and puts a space on the canvas cell representing it. Because output in pb is 2D, the empty cells before it are automatically filled in with spaces when it's outputted.

answered May 25 '17 at 19:26

undergroundmonorail

5,8672 gold badges25 silver badges50 bronze badges

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Samuel · Accepted Answer · 2017-05-25 20:37:11Z

1

x64 ASSEMBLY (linux nasm) - 131 bytes

mov r8, [rsp+16]
mov rdi, 1
mov rdx, 1
mov rax, 1
mov rsi,n
l:syscall
inc r8
cmp byte [r8],0x00
jnz l
mov rax,60
syscall
n: db " "

build and run with:

nasm -felf64 invisible_golfed.asm
ld invisible_golfed.asm
./a.out

This will give the warning

ld: warning: cannot find entry symbol _start; defaulting to 00000000000400080

warning free version below

without warnings - 152

global _start
_start:mov r8, [rsp+16]
mov rdi, 1
mov rdx, 1
mov rax, 1
mov rsi,n
l:syscall
inc r8
cmp byte [r8],0x00
jnz l
mov rax,60
syscall
n: db " "

answered May 25 '17 at 20:37

Samuel

1914 bronze badges

\$\begingroup\$ When I give the program "When I give the program" on STDIN, it only prints a single space. I suggest your read the I/O defaults and revise your answer. Essentially, revise your code to take input from STDIN. \$\endgroup\$ – CalculatorFeline May 26 '17 at 3:15
\$\begingroup\$ My bad I have it reading from the command line. I'll fix that tomorow when I get the chance. \$\endgroup\$ – Samuel May 26 '17 at 4:46
1

\$\begingroup\$ Your byte-counting is not correct. With assembly language, we count th bytes of the machine code that is generated, not the characters in the instruction mnemonics. Beyond that problem, there's lots of room for optimization here. Save several bytes by changing instructions of the form MOV Rxx, x to MOV Exx, x, where x is an immediate value <= 32 bits, taking advantage of the fact that the upper 32-bits of a 64-bit register are implicitly cleared. I also don't know why you define n separately, instead of embedding it into the instruction: MOV ESI, ' '. That gets me down to 48 bytes. \$\endgroup\$ – Cody Gray May 26 '17 at 12:01
\$\begingroup\$ You can save even more by changing all but the first instruction in the MOV reg, 1 sequence to a reg-reg move, which has a much shorter encoding: mov eax, 1+mov edx, eax+mov edi, eax. That's only 36 bytes. \$\endgroup\$ – Cody Gray May 26 '17 at 12:04

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MD XF · Accepted Answer · 2017-05-26 02:29:32Z

1

C, 57 33 30 bytes

-3 thanks to Tas.

f(int*a){while(*a++)puts("");}

Try it online!

edited May 26 '17 at 2:29

answered May 25 '17 at 22:15

MD XF

11.5k2 gold badges53 silver badges97 bronze badges

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briantist · Accepted Answer · 2017-05-26 04:09:39Z

1

PowerShell, 18 bytes

' '*"$args".Length

Try it online!

answered May 26 '17 at 4:09

briantist

3,11010 silver badges21 bronze badges

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spark · Accepted Answer · 2017-05-26 08:53:34Z

1

Python, 23 bytes

print(''*len(input()))

First time

edited May 26 '17 at 8:53

answered May 26 '17 at 7:36

spark

1114 bronze badges

\$\begingroup\$ Assuming where input comes from is usually frowned upon here. You need to wrap the code in a program/method or ask the user for input. \$\endgroup\$ – TheLethalCoder May 26 '17 at 8:25
\$\begingroup\$ @TheLethalCoder fixed! \$\endgroup\$ – spark May 26 '17 at 8:31
\$\begingroup\$ You don't need the space between , and ' in your second version. However, that second version isn't a full program - you need a print call, and you need to fix your str.replace call (not enough arguments). \$\endgroup\$ – Mego May 26 '17 at 8:50

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Delya Erricson · Accepted Answer · 2017-05-26 18:48:05Z

1

Lua, 17 Bytes

s=s:gsub("."," ")

Simple regular expression substitution, replaces any character found with a space.

answered May 26 '17 at 18:48

Delya Erricson

811 silver badge3 bronze badges

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streetster · Accepted Answer · 2017-06-12 22:22:08Z

q/kdb+, 14 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}'" "
"           "

Lynn · Accepted Answer · 2018-06-23 12:01:33Z

Z80Golf, 9 bytes

00000000: d5cd 0380 3001 763e 20                   ....0.v>

Try it online!

Disassembly:

  push de     ; push $0000
  call $8003  ; getchar(A)
  jr nc, k    ; jump if not EOF
  halt
k:ld a, ' '   ; replace A with space
              ; memory from $000a through $7fff is $00=NOP...
              ; PC reaches $8000=putchar(A) and RETs to pushed address.

(If you remove the last two bytes, this is a cat program.)

Sophia Lechner · Accepted Answer · 2018-07-10 19:37:38Z

dc, 12 bytes

Z256r^25.5/P

Try it online!

Takes input from the stack, outputs newlines to stdin.

I know there's two dc answers here already, but this one uses a different approach, with math! Plus it's 6 bytes shorter, so I guess that's all right.

Explanation

One of dc's three explicit printing commands is P, which takes a number and outputs it as a base 256 (technically base UCHAR_MAX+1, works on my machine) byte stream. So I need to feed it the number (where n is the length of the given string, and 10 is the codepoint of the linefeed character):

   10*256^(n-1) + 10*256^(n-2) + ... + 10
 = 10 * (256^(n-1) + 256^(n-2) + ... + 1)   (factoring out 10)
 = 10 * (256^n - 1) / (256 - 1)             (geometric series formula)
 = (256^n - 1) / 25.5                       (combining constants)    
~= (256^n) / 25.5                           (because dc's default precision is 0)

The code is a straightforward calculation of this number, followed by P.

Argh, doesn't handle the empty string (P outputs a NUL when it pops a 0). I guess I could say it's outputting a null-terminated string...seems like a stretch though. — Sophia Lechner, Jul 10 '18 at 19:43
Also, it's only on TIO that you can tell. On my machine a NUL gets eaten silently so it works. I still feel badly about it. — Sophia Lechner, Jul 10 '18 at 19:57

PieCot · Accepted Answer · 2018-07-10 22:51:21Z

1

Octave / Matlab, 25 23 bytes

@(x)repmat(' ',size(x))

_{Saved 2 bytes thanks to Giuseppe}

Try it online!

edited Jul 10 '18 at 22:51

answered Jul 10 '18 at 20:47

PieCot

1,0295 silver badges10 bronze badges

\$\begingroup\$ I think the f= is unnecessary; anonymous functions / function handles are perfectly acceptable on PPCG. \$\endgroup\$ – Giuseppe Jul 10 '18 at 22:27
\$\begingroup\$ You can also include a link to Try it online! for Octave so others can test your answer. \$\endgroup\$ – Giuseppe Jul 10 '18 at 22:28

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Syed Hamza Hassan · Accepted Answer · 2018-10-23 05:07:11Z

1

Java (JDK), 84 bytes

static String m(String n){int i=0;String d="";while(i++<n.length())d+=" ";return d;}

Try it online!

edited Oct 23 '18 at 5:07

answered Oct 22 '18 at 9:41

Syed Hamza Hassan

1294 bronze badges

\$\begingroup\$ Updated Sir @JoKing. \$\endgroup\$ – Syed Hamza Hassan Oct 22 '18 at 12:08
\$\begingroup\$ This does not address my other concerns, i.e. initialising d and reusing the function. Also, wouldn't it be shorter to use an anonymous lambda? \$\endgroup\$ – Jo King Oct 22 '18 at 12:14
\$\begingroup\$ Your suggestions are so useful, Thanks @JoKing \$\endgroup\$ – Syed Hamza Hassan Oct 23 '18 at 5:07

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a'_' · Accepted Answer · 2019-11-15 03:54:14Z

1

Wren, 22 bytes

Multiply the space by the length of the string.

Fn.new{|a|" "*a.count}

Try it online!

answered Nov 15 '19 at 3:54

a'_'

6,8722 gold badges14 silver badges48 bronze badges

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Dorian · Accepted Answer · 2019-11-15 12:29:15Z

Brain-Flak, 28 bytes

{}{{}<>((()()()()()){})<>}<>

Try it online!

{}                  pop one input character (because Brain-Flak always outputs a trailing newline
{                   for each input character
  {}                pop that character
  <>                switch to other stack
  ((()()()()()){})  push 10 (newline)
  <>                back to input stack
}
<>                  switch to other stack. This is printed implicitly when the program ends

Jono 2906 · Accepted Answer · 2019-11-16 04:48:27Z

1

Keg,`-lp` `-ir`, 3 bytes

( ,

Try it online!

This takes input as characters and prints a space for each character The -lp flag makes the length() function take input if the stack is empty and the -ir flag ensures that the implicit input is as characters.

edited Nov 16 '19 at 4:48

answered Nov 15 '19 at 2:38

Jono 2906

3,7971 gold badge9 silver badges41 bronze badges

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theblitz · Accepted Answer · 2017-05-25 21:07:07Z

0

REXX 27 Bytes

say left("",length(arg(1)))

answered May 25 '17 at 21:07

theblitz

1,2012 gold badges3 silver badges7 bronze badges

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Shaun Bebbers · Accepted Answer · 2017-05-26 05:54:44Z

0

ZX80 (4K ROM version with sanity check)

~58 bytes (listing)

 1 INPUT A$
 2 IF A$="" THEN GO TO 1
 3 PRINT " ";
 4 LET A$=TL$(A$)
 5 IF A$="" THEN STOP
 6 GO TO 3

Line 2 can be removed to save RAMs. However, if an empty string is entered without line 2 then it will PRINT one space.

edited May 26 '17 at 5:54

answered May 25 '17 at 16:12

Shaun Bebbers

1,7647 silver badges20 bronze badges

\$\begingroup\$ It is now later. \$\endgroup\$ – CalculatorFeline May 26 '17 at 3:08

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Kaz · Accepted Answer · 2017-05-27 01:35:18Z

0

TXR Lisp, 22 19 bytes:

(op regsub #/./" ")

Previously:

(op mapcar(ret[" "0]))

That is a function to which we can pass a string:

REPL:

1> (op regsub #/./" ")
#<interpreted fun: lambda #:rest-0164>
2> [*1 "abc"]
"   "

"   "

edited May 27 '17 at 1:35

answered May 27 '17 at 1:29

Kaz

3721 silver badge8 bronze badges

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madstap · Accepted Answer · 2017-05-29 05:47:20Z

0

Clojurescript, 27 bytes

#(apply str(map(fn[]" ")%))

Because it's based on js, clojurescript doesn't care about arity errors. That saves one byte over the clojure eqivalent.

answered May 29 '17 at 5:47

madstap

1412 bronze badges

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stevefestl · Accepted Answer · 2017-05-30 06:08:31Z

0

Windows batch, 115 bytes

@set i=%~1
@set p=0
@set/ac=-1
:N
@call set t=%%i:~%p%,1%%
@set/ac+=1
@set/ap+=1
@if "%t%" NEQ "" @goto N
@echo %c%

Re-used code from my answer in Is the checkbox not not unchecked?

answered May 30 '17 at 6:08

stevefestl

5393 silver badges12 bronze badges

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markasoftware · Accepted Answer · 2017-05-30 18:41:37Z

0

Bash + Coreutils, 11 Bytes

tr -c \ \

answered May 30 '17 at 18:41

markasoftware

3461 silver badge7 bronze badges

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Esolanging Fruit · Accepted Answer · 2017-05-30 21:44:05Z

Check, 6 bytes (non-competing)

," "*o

This is non-competing as I just made Check yesterday.

Pass the input by the command-line arguments as a list of code points, i.e. [72,101,108,108,111,44,32,87,111,114,108,100,33].

Explanation:

, gets the length of the input.
" " pushes an array containing 32 (for space).
* repeats that array as many times as the length of the input.
o displays the result as a list of characters.

Sivaprasath Vadivel · Accepted Answer · 2017-06-01 06:51:19Z

0

Powershell, 22 Bytes

' '*(Read-Host).length

edited Jun 1 '17 at 6:51

answered May 26 '17 at 8:46

Sivaprasath Vadivel

1392 bronze badges

1

\$\begingroup\$ Not sure if Read-Host counts for input but " "*"$args".length is shorter anyway. Also there is not len property. That should be printing nulls. \$\endgroup\$ – Matt May 30 '17 at 12:17
\$\begingroup\$ Length property and Len are same \$\endgroup\$ – Sivaprasath Vadivel May 30 '17 at 13:32
\$\begingroup\$ "hello".Len is null on my system because that is a non-existent property where as "hello".Length returns 5. If that works for you then you have an alias or extent that I, and most, do not have. \$\endgroup\$ – Matt May 30 '17 at 14:14
\$\begingroup\$ Ok...That explains it \$\endgroup\$ – Sivaprasath Vadivel May 30 '17 at 14:15

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Value Ink · Accepted Answer · 2017-06-07 20:33:29Z

0

Ruby, 12 11+1 = 13 12 bytes

Uses the -p flag. -1 byte from Martin Ender.

gsub /./,$/

Try it online!

edited Jun 7 '17 at 20:33

answered May 30 '17 at 8:05

Value Ink

10.4k8 silver badges40 bronze badges

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Conor O'Brien · Accepted Answer · 2017-06-12 23:45:37Z

0

J, 6 bytes

' '#~#

Try it online!

Explanation

' '#~#
   #~    repeat
' '      spaces
     #   for length of input

answered Jun 12 '17 at 23:45

Conor O'Brien

36.1k2 gold badges71 silver badges165 bronze badges

\$\begingroup\$ 4 bytes ''"0 outputs n newlines. \$\endgroup\$ – FrownyFrog Oct 28 '17 at 1:07
\$\begingroup\$ @FrownyFrog You should make your own answer, it's quite different from mine \$\endgroup\$ – Conor O'Brien Oct 28 '17 at 3:51

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Print invisible text

Testcases:

Scoring:

102 Answers 102

SmileBASIC 3, 22 bytes

Mathematica, 30 bytes

Lua, 25 bytes

tcl, 19

Rust, 23 bytes

Brain-Flak, 28 bytes

pb - 17 bytes

x64 ASSEMBLY (linux nasm) - 131 bytes

C, 57 33 30 bytes

PowerShell, 18 bytes

Lua, 17 Bytes

q/kdb+, 14 9 bytes

Z80Golf, 9 bytes

dc, 12 bytes

Explanation

Octave / Matlab, 25 23 bytes

Java (JDK), 84 bytes

Wren, 22 bytes

Brain-Flak, 28 bytes

Keg,-lp -ir, 3 bytes

REXX 27 Bytes

ZX80 (4K ROM version with sanity check)

Clojurescript, 27 bytes

Windows batch, 115 bytes

Check, 6 bytes (non-competing)

Powershell, 22 Bytes

Ruby, 12 11+1 = 13 12 bytes

J, 6 bytes

Explanation

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