Write a program to elasticize strings

Question

Nice verb there, in the title.

Write a program that given an input string, will "elasticize" this string and output the result. Elasticizing a string is done as follows:

The first character is shown once. The second character is shown twice. The third character is shown thrice, and so on.

As you can see, the amount of duplications of a certain character is related to the character's index as opposed to its previous occurrences in the string.

You can expect to receive only printable ASCII characters. Based off the following link, these characters have decimal values 32-126.

Examples:

Why: Whhyyy

SKype: SKKyyyppppeeeee

LobbY: LoobbbbbbbYYYYY (Note how there are 7 b's since the first b is shown 3 times and the second b is shown 4 times, making a total of 7 b's).

A and B: A aaannnnddddd BBBBBBB

Shortest bytes wins :)

That seems to disagree with "no support for whitespace is needed, other than the space character". Should the output be the same as the input then? (Two one letter words?) Also note we have a nice place called the Sandbox where you can put challenges for people to give you feedback before posting them. — FryAmTheEggman, Jun 20, 2016 at 19:50
FryAmTheEggman your assumption is valid. @TimmyD I realize where I was unclear, you may end up with strings separated my multiple spaces, as seen in the example FryAmTheEggman posted. — Mario Ishac, Jun 20, 2016 at 19:52
@Adnan Yep, though I'm not sure if I should mark the answer with the shorted program as accepted, as certain languages are made for golfing purposes unlike others. — Mario Ishac, Jun 20, 2016 at 19:56

ScifiDeath · Accepted Answer · 2016-06-20 20:48:31Z

2

C#, 81 Bytes

void f(string s){for(int i=0;i<s.Length;i++)Console.Write(new String(s[i],i+1));}

answered Jun 20, 2016 at 20:48

ScifiDeath

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\$\begingroup\$ you can save 1 byte by changing to a foreach loop, e.g. foreach(var a in s)Console.Write(new C(a,1*i++)); \$\endgroup\$
– Abbath
Jun 20, 2016 at 23:09
\$\begingroup\$ but if its a foreach we don't have the i variable so you'd need to declare it. \$\endgroup\$
– ScifiDeath
Jun 21, 2016 at 9:43
\$\begingroup\$ It seems you're missing a using System or a System. in front of the Console. \$\endgroup\$
– Martin Ender
Jun 21, 2016 at 11:36
\$\begingroup\$ @ScifiDeath That's true - but the end result is still one byte shorter. Sorry for omitting it and causing confusion int i=1; \$\endgroup\$
– Abbath
Jun 21, 2016 at 13:56
\$\begingroup\$ Also one byte shorter using Linq: void f(string s){s.Select((c,i)=>{Console.Write(new string(c,i+1));return c;});}. The need for a (unused) return value is ugly though. Edit: just found similar snippets in other answers further back. \$\endgroup\$
– linac
Jun 22, 2016 at 15:20

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Community · Accepted Answer · 2020-06-17 09:04:33Z

2

MATL, 5 bytes

tn:Y"

Try it Online

Explanation

    % Implictly grab input as a string
tn  % Duplicate and compute the length (N)
:   % Create an array from [1...N]
Y"  % Perform run-length decoding to elacticize the string
    % Implicitly display the result

edited Jun 17, 2020 at 9:04

CommunityBot

1

answered Jun 20, 2016 at 21:06

Suever

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Community · Accepted Answer · 2020-06-17 09:04:33Z

2

Python, 40 bytes

f=lambda s,i=1:s and s[0]*i+f(s[1:],i+1)

edited Jun 17, 2020 at 9:04

CommunityBot

1

answered Jun 21, 2016 at 1:07

xnor

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Dennis · Accepted Answer · 2016-06-21 04:12:53Z

2

Julia, 34 bytes

!s=s>""?!s[1:(e=end)-1]*s[e:e]^e:s

Try it online!

answered Jun 21, 2016 at 4:12

Dennis

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\$\begingroup\$ Your solution was good. But I managed to beat it. \$\endgroup\$
– Glen O
Jun 21, 2016 at 9:24
\$\begingroup\$ I saw. I had c%n="$c"^n;~s=join([s[r=1:end]...].%r), but that's actually longer. split was the missing piece of the puzzle. \$\endgroup\$
– Dennis
Jun 21, 2016 at 15:00

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t-clausen.dk · Accepted Answer · 2016-06-21 08:40:37Z

2

TSQL, 97 bytes

Golfed:

DECLARE @x varchar(max)='Lobby'
DECLARE @ int=LEN(@x)WHILE @>0SELECT
@x=STUFF(@x,@,1,REPLICATE(SUBSTRING(@x,@,1),@)),@-=1PRINT @x

Ungolfed:

DECLARE @x varchar(max)='Lobby'

DECLARE @ int=LEN(@x)
WHILE @>0
  SELECT 
    @x=STUFF(@x,@,1,REPLICATE(SUBSTRING(@x,@,1),@)),
    @-=1

PRINT @x

Try it online

answered Jun 21, 2016 at 8:40

t-clausen.dk

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LLlAMnYP · Accepted Answer · 2016-06-21 10:00:06Z

Mathematica, 46 bytes

""<>Table@@@(#^Range@Length@#&@Characters[#])&

Unnamed function. Takes the characters of the input string and raises them to the power of their position in the string (i.e. "abc" becomes {"a"^1, "b"^2, "c"^3}). Yes, MMA don't give a shit 'bout types :-)

The FullForm of the above list elements is Power["a", 1], etc.
Table@@@ acts on the list, replacing the head of each element (in this case Power) with Table.
Results in {Table["a"], Table["b", 2], Table["c", 3]} (because "a"^1 -> "a").
This evaluates to {"a", {"b", "b"}, {"c", "c", "c"}} Finally the infix concatenation operator <> concatenates this with the empty string.

I exploited the fact that Power is Listable, i.e. it automatically threads over corresponding elements of lists, but not orderless (because "a" + 1 would evaluate to Plus[1, "a"]).

Community · Accepted Answer · 2020-06-17 09:04:33Z

2

LINQPad w/ C#, 82 bytes

void m(string s){Console.Write(s.SelectMany((x,i)=>new string(x,++i)).ToArray());}

Single output operation.

edited Jun 17, 2020 at 9:04

CommunityBot

1

answered Jun 21, 2016 at 11:13

Søren D. Ptæus

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\$\begingroup\$ @MartinEnder using System; & using System.Linq; are not necessary in LINQPad. \$\endgroup\$
– Søren D. Ptæus
Jun 21, 2016 at 12:05
\$\begingroup\$ Oh, I wasn't aware of that. \$\endgroup\$
– Martin Ender
Jun 21, 2016 at 12:19

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jqkul · Accepted Answer · 2016-06-21 20:20:40Z

C, 84 bytes

main(c,v,i,j)char**v;{for(i=0;i<strlen(v[1]);++i)for(j=0;j<=i;++j)putchar(v[1][i]);}

This should compile on gcc with no flags. Input is taken through the first command-line argument. E.g.

$ ./elasticize Why
Whhyyy
$ ./elasticize SKype
SKKyyyppppeeeee
$ ./elasticize LobbY
LoobbbbbbbYYYYY
$ ./elasticize A and B
A  aaannnnddddd      BBBBBBB

Ungolfed:

int main(int argc, char** argv) {
    int i, j;
    for(i = 0; i < strlen(argv[1]); ++i) {
        for(j = 0; j <= i; ++j) {
            putchar(v[1][i]);
        }
    }
}

cliffroot · Accepted Answer · 2016-06-22 09:23:44Z

2

Clojure, 86 bytes

(fn[s](apply str(mapcat #(repeat(+(nth % 1)1)(nth % 0))(map list s(range(count s))))))

Well, nearly beat C. Create a list of pairs (symbol, its position), then repeat each symbol given number of times and flatten the result list and concatenate the list into one string.

See it here: https://ideone.com/uQNar2

answered Jun 22, 2016 at 9:23

cliffroot

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emanresu A · Accepted Answer · 2022-08-20 07:34:19Z

2

Jelly, 2 bytes

xJ

Try it online!

edited Aug 20, 2022 at 7:34

emanresu A

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answered Mar 15, 2017 at 12:33

Erik the Outgolfer

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\$\begingroup\$ Why non-competing? it's completely okay. \$\endgroup\$
– Matthew Roh
Mar 17, 2017 at 8:02
\$\begingroup\$ @MatthewRoh J did not exist back then. \$\endgroup\$
– Erik the Outgolfer
Mar 17, 2017 at 12:28

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user114260user114260 · Accepted Answer · 2022-08-21 03:31:48Z

2

Dart, 47 bytes

f(s,[c=0])=>s.split("").map((i)=>i*++c).join();

Try it online!

answered Aug 21, 2022 at 3:31

user114260

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Sampersand · Accepted Answer · 2022-08-21 04:37:51Z

2

+100

Knight, 33 32 bytes

;=i!=sP;W<iLsO+*Gs iT=i+1i"\"O""

Try it online!

expanded:

; = i ! = s PROMPT
; WHILE < i LENGTH s
    : OUTPUT
        +
            * (GET s i TRUE) (= i + 1 i)
        "\" # so no trailing newline
: OUTPUT "" # now output the trailing newline

-1 did =i! instead of ;=iF

edited Aug 21, 2022 at 4:37

answered Aug 21, 2022 at 4:05

Sampersand

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\$\begingroup\$ You forgot to put =i+1i in your expanded version. \$\endgroup\$
– Aiden Chow
Aug 21, 2022 at 4:35
\$\begingroup\$ Yo that ! thing is actually super smart. \$\endgroup\$
– Aiden Chow
Aug 21, 2022 at 4:38
\$\begingroup\$ Why do you have to output a trailing newline? No one said you did. \$\endgroup\$
– naffetS
Aug 21, 2022 at 18:27

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Shaggy · Accepted Answer · 2022-11-16 16:45:44Z

2

Japt `-m`, 3 bytes

+pV

Try it here

answered Nov 16, 2022 at 16:45

Shaggy

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pxeger · Accepted Answer · 2023-01-29 10:33:59Z

2

Zsh, 38 bytes

for i (${(s::)@});repeat ++n printf $i

Try it online!

-8 bytes thanks to roblogic

edited Jan 29 at 10:33

answered Feb 16, 2021 at 20:29

pxeger

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\$\begingroup\$ 41 bytes \$\endgroup\$
– roblogic
Jan 28 at 15:28

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c-- · Accepted Answer · 2023-02-22 04:15:58Z

2

C (clang), 54 bytes

i;c;main(j){for(;j=j-1?:read(0,&c,1)*++i;)putchar(c);}

Try it online!

How it works

i;            // declares a zero initialized int
main(j){      // j := argc (should be 1, program called with no arguments)
 for(;j=j-1?: // if (j > 1) j = j - 1, otherwise...
 read(0,&c,1) // try to read 1 byte, return number of bytes read (0 on EOF or 1)
 *++i;)       // increment i, j = read? * i (stopping on EOF)
  putchar(c); // write to stdout
}

C (clang), 51 bytes

With help from @Steffan and @jdt.

i,j;f(*s){for(i=0;*s;s++)for(j=++i;j--;)printf(s);}

This function takes a wide-character string as input and works in the same way as the full program.

Try it online!

edited Feb 22 at 4:15

answered Aug 21, 2022 at 16:00

c--

2,4231 gold badge4 silver badges15 bronze badges

\$\begingroup\$ This is pretty interesting, but it's 54 bytes to declare a function and write to stdout: Try it online! \$\endgroup\$
– naffetS
Aug 21, 2022 at 20:23
1

\$\begingroup\$ you'd need to reset i=0 if you want the ability to call the function more than once \$\endgroup\$
– c--
Aug 21, 2022 at 20:29
\$\begingroup\$ 53 bytes \$\endgroup\$
– jdt
Aug 22, 2022 at 18:47

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Community · Accepted Answer · 2020-06-17 09:04:33Z

1

05AB1E, 6 bytes

vN>Fy?

Explained

v       # for each char in string
 N>F    # index+1 number of times do
    y?  # print current char

Try it online

edited Jun 17, 2020 at 9:04

CommunityBot

1

answered Jun 20, 2016 at 20:01

Emigna

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1

\$\begingroup\$ This one looks like it has a question :D \$\endgroup\$
– SE is dead
Jun 20, 2016 at 20:10

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Community · Accepted Answer · 2020-06-17 09:04:33Z

1

Retina, 62 bytes

It wasn't as easy or short as I thought it'd be. Note that the code contains no spaces. They are all tabs (which are rendered incorrectly here), and the last line is blank.

.*
$0¶ ¶
{+`^(.)(.*)¶    (.*¶.*)
$1$2    ¶$3$1
(   +)¶
¶   $1
}`^.

    |¶

Try it online

edited Jun 17, 2020 at 9:04

CommunityBot

1

answered Jun 20, 2016 at 22:04

mbomb007

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Community · Accepted Answer · 2020-06-17 09:04:33Z

1

Ruby, 29 bytes

Try it online

->s{i=0;s.gsub(/./){$&*i+=1}}

edited Jun 17, 2020 at 9:04

CommunityBot

1

answered Jun 21, 2016 at 4:30

Value Ink

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Community · Accepted Answer · 2020-06-17 09:04:33Z

1

Pyke, 4 bytes

Foh*

Try it here!

edited Jun 17, 2020 at 9:04

CommunityBot

1

answered Jun 21, 2016 at 6:09

Blue

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Swadhikar · Accepted Answer · 2016-06-21 06:53:16Z

1

Python 2.7 - 47 Bytes

''.join([s[i-1]*i for i in range(1, len(s)+1)])

where 's' is the given string Output:

welcome: weelllccccooooommmmmmeeeeeee
00004:   000000000044444
Why:     Whhyyy
SKype:   SKKyyyppppeeeee
A and B: A  aaannnnddddd      BBBBBBB

answered Jun 21, 2016 at 6:53

Swadhikar

1314 bronze badges

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Jeto · Accepted Answer · 2016-06-21 12:24:21Z

1

Oracle SQL 11.2, 125 bytes

SELECT LISTAGG(SUBSTR(RPAD(' ',LEVEL+1,SUBSTR(:1,LEVEL,1)),2))WITHIN GROUP(ORDER BY 1)FROM DUAL CONNECT BY LEVEL<=LENGTH(:1);

answered Jun 21, 2016 at 12:24

Jeto

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Community · Accepted Answer · 2020-06-17 09:04:33Z

1

C, 77 bytes

Not much room for golfing here. If only there were a string repeat operator.

i;main(j){char s[999];gets(s);for(;s[i];i++)for(j=0;j<=i;j++)putchar(s[i]);}

Try it online! http://ideone.com/UliJfD

edited Jun 17, 2020 at 9:04

CommunityBot

1

answered Jun 22, 2016 at 22:06

homersimpson

2812 silver badges4 bronze badges

\$\begingroup\$ You can do i;main(j){... and save a bye \$\endgroup\$
– cat
Jun 23, 2016 at 23:06
\$\begingroup\$ @cat Good idea; thanks! \$\endgroup\$
– homersimpson
Jun 29, 2016 at 22:26

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Sandra · Accepted Answer · 2022-08-20 08:34:19Z

1

brev, 42 bytes

(as-list flatten(over(make-list(+ i 1)x)))

answered Aug 20, 2022 at 8:34

Sandra

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DeathIncarnate · Accepted Answer · 2022-08-22 19:08:58Z

1

Burlesque, 10 bytes

{+..*}wi\[

Try it online!

{
 +. # Increment
 .* # Repeat
}wi # Apply with 0-index
\[  # Concatenate

answered Aug 22, 2022 at 19:08

DeathIncarnate

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Ivan Neeson · Accepted Answer · 2022-08-23 04:21:44Z

1

C# (Visual C# Interactive Compiler), 53 bytes

a=>string.Concat(a.Select((c,i)=>new@String(c,i+1)));

Try it online!

answered Aug 23, 2022 at 4:21

Ivan Neeson

1913 bronze badges

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Leaf · Accepted Answer · 2022-08-27 09:56:28Z

1

Kustom, 67 bytes

This makes use of the fact that an undefined global variable works as empty string. The extra byte is for the name of the defined global variable.

$fl(1,tc(len,gv(n)),"i+1","tc(lpad,gv(x),i,tc(cut,gv(n),i-1,1))")$

Sort of ungolfed:

$fl(
  1,
  tc(len, gv(input)),
  "i + 1",
  "tc(
    lpad,
    gv(undefined),
    i,
    tc(
      cut,
      gv(input),
      i - 1,
      1
    )
  )"
)$

edited Aug 27, 2022 at 9:56

answered Aug 26, 2022 at 14:00

Leaf

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naffetS · Accepted Answer · 2022-08-27 20:40:12Z

1

Prolog (SWI), 69 bytes

S*O:-append(H,[T],S),maplist([_,Y]>>(Y=T),S,R),H*Y,append(Y,R,O);O=S.

Try it online!

I feel like this should be shorter...

edited Aug 27, 2022 at 20:40

answered Aug 27, 2022 at 20:30

naffetS

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Baby_Boy · Accepted Answer · 2022-11-16 16:16:42Z

1

Pip, 14 bytes

Fi,#aOa@iXi+1x

Try It Online!

answered Nov 16, 2022 at 16:16

Baby_Boy

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chunes · Accepted Answer · 2023-01-28 10:02:18Z

1

Arturo, 44 bytes

$[s][i:0join map split s'c[i:i+1repeat c i]]

Try it

answered Jan 28 at 10:02

chunes

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The Thonnu · Accepted Answer · 2023-01-28 10:18:55Z

1

Thunno `J`, \$9\log_{256}(96)\approx\$ 7.41 bytes

DLR1+ZZ.P

Attempt This Online!

Explanation

DLR1+ZZ.P  # Implicit input
D          # Duplicate
 LR        # Push range(0, len(input))
   1+      # Add one to each
     ZZ    # Zip with the input
       .P  # Product of each pair
           # Implicit output, joined by J flag

answered Jan 28 at 10:18

The Thonnu

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Stack Exchange Network

Write a program to elasticize strings

67 Answers 67

C#, 81 Bytes

MATL, 5 bytes

Python, 40 bytes

Julia, 34 bytes

TSQL, 97 bytes

Mathematica, 46 bytes

LINQPad w/ C#, 82 bytes

C, 84 bytes

Clojure, 86 bytes

Jelly, 2 bytes

Dart, 47 bytes

Knight, 33 32 bytes

Japt `-m`, 3 bytes

Zsh, 38 bytes

C (clang), 54 bytes

How it works

C (clang), 51 bytes

05AB1E, 6 bytes

Retina, 62 bytes

Ruby, 29 bytes

Pyke, 4 bytes

Oracle SQL 11.2, 125 bytes

C, 77 bytes

brev, 42 bytes

Burlesque, 10 bytes

C# (Visual C# Interactive Compiler), 53 bytes

Kustom, 67 bytes

Prolog (SWI), 69 bytes

Pip, 14 bytes

Arturo, 44 bytes

Thunno `J`, \$9\log_{256}(96)\approx\$ 7.41 bytes

Explanation

Your Answer

Not the answer you're looking for? Browse other questions tagged
code-golf
string
or ask your own question.

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Hot Network Questions

Write a program to elasticize strings

67 Answers 67

C#, 81 Bytes

MATL, 5 bytes

Python, 40 bytes

Julia, 34 bytes

TSQL, 97 bytes

Mathematica, 46 bytes

LINQPad w/ C#, 82 bytes

C, 84 bytes

Clojure, 86 bytes

Jelly, 2 bytes

Dart, 47 bytes

Knight, 33 32 bytes

Japt -m, 3 bytes

Zsh, 38 bytes

C (clang), 54 bytes

How it works

C (clang), 51 bytes

05AB1E, 6 bytes

Retina, 62 bytes

Ruby, 29 bytes

Pyke, 4 bytes

Oracle SQL 11.2, 125 bytes

C, 77 bytes

brev, 42 bytes

Burlesque, 10 bytes

C# (Visual C# Interactive Compiler), 53 bytes

Kustom, 67 bytes

Prolog (SWI), 69 bytes

Pip, 14 bytes

Arturo, 44 bytes

Thunno J, \$9\log_{256}(96)\approx\$ 7.41 bytes

Explanation

Your Answer

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Not the answer you're looking for? Browse other questions tagged code-golfstring or ask your own question.

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Related

Hot Network Questions

Japt `-m`, 3 bytes

Thunno `J`, \$9\log_{256}(96)\approx\$ 7.41 bytes

Not the answer you're looking for? Browse other questions tagged
code-golf
string
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