How to pluralize ellipsis?

Question

It's obviously ellipsisessieses.

Inspired by a chat message.

Your challenge

Given a list or space or comma-separated string of words, ellipsisessiesesify them.

To ellipsisessieses-ify a word:

1. Start with the word.
2. Add the first letter of the original word to the end.
3. Add 2 of the last letter of the original word to the end.
4. Add the second-to-last letter of the original word to the end.
5. Add the first letter of the original word to the end.
6. Add the last letter of the original word to the end.
7. Repeat steps 5 & 6 once.
8. You're done!

You can assume:

• The input words will only be alphanumeric
• Input & output can be a space-separated string or list
• The input will contain only words
• The words will be at least 2 letters long
• The input will match the regex /^[a-z0-9]{2,}( [a-z0-9]{2,})*$/i
• You can have a different input and output format
• More to come...

Test cases:

ellipsis -> ellipsisessieses
goat -> goatgttagtgt
covfefe -> covfefeceefcece
programmer5000 -> programmer5000p000p0p0
up vote down goat -> upuppuupup voteveetveve downdnnwdndn goatgttagtgt
it is golf yo -> itittiitit isissiisis golfgfflgfgf yoyooyyoyo
crossed out 44 is still 44 -> crossedcddecdcd outottuotot 4444444444 isissiisis stillslllslsl 4444444444

Shorteststtsstst answerarrearar ininniinin bytesbssebsbs winswssnwsws!

Answer 1

JavaScript (ES6), 58 57 bytes

NB: This turns out to use the same trick as Jonathan Allan in this Jelly answer (though I noticed after posting).

Saved 1 byte thanks to Jonathan Allan

Works on arrays of strings.

s=>s.map(s=>s+'01120101'.replace(/./g,n=>s.substr(-n,1)))

Test cases

let f =

s=>s.map(s=>s+'01120101'.replace(/./g,n=>s.substr(-n,1)))

console.log(f(['ellipsis']))
console.log(f(['goat']))
console.log(f(['covfefe']))
console.log(f(['programmer5000']))
console.log(f(['up', 'vote', 'down', 'goat']))
console.log(f(['it', 'is', 'golf', 'yo']))
console.log(f(['crossed', 'out', '44', 'is', 'still', '44']))

Answer 2

Jelly,  13 12  11 bytes

⁽×ʠb3’ịṭµ€K

A full program that takes a list of lists of characters and prints the space separated output.

Try it online!

How?

⁽×ʠb3’ịṭµ€K - Main link: list of lists of characters e.g. ["this","is","it"]
        µ€  - for each word in the input:            e.g. "this"
⁽×ʠ         -   base 250 literal 5416                     5416
   b3       -   converted to base 3                       [2,1,1,0,2,1,2,1]
     ’      -   decrement                                 [1,0,0,-1,1,0,1,0]
      ị     -   index into the word                       "tssitsts"
       ṭ    -   tack to the word                          ["this",["tssitsts"]]
          K - join the results with spaces                ["this",["tssitsts"]," is",["issiisis"]," it",["ittiitit"]]
            - implicit print                              thistssitsts isissiisis itittiitit

---

Alternatively a list of words to list of words is also possible in 11 bytes:

⁽×ʠb3’ị;@µ€

⁽×ʠb3’ may also be replaced by 4,⁵Bj- for the same byte count
([4,10] in binary is [[1,0,0],[1,0,1,0]] joined by -1 is [1,0,0,-1,1,0,1,0]).

Answer 3

05AB1E, 12 bytes

εD•Lz•3вÍèJ«

Try it online!

Explanation

ε              # apply on each word in input
 D             # duplicate the word
  •Lz•         # push the base-255 compressed number 5416
      3в       # convert to a list of base-3 digits (yields [2, 1, 1, 0, 2, 1, 2, 1])
        Í      # subtract 2 from each (yields [0, -1, -1, -2, 0, -1, 0, -1])
         è     # index into the word with these numbers
          J    # join to string
           «   # append to the original word

Answer 4

Retina, 52 49 bytes

3 bytes thanks to Arnauld.

(\w)(\w+)
$1$2$1
(.)(.)(.)\b
$1$2$3$2$2$1$3$2$3$2

Try it online!

Answer 5

Python 2, 56 bytes

lambda s:[i+i[0]+i[-1]*2+i[-2]+(i[0]+i[-1])*2for i in s]

Try it online!

I think this is my fastest FGITW and it's not even that impressive. :P

Answer 6

Python 3, 60 bytes

lambda k:[x+''.join(x[-int(i)]for i in"01120101")for x in k]

Try it online!

Answer 7

Charcoal, 20 bytes

Ｆ⪪Ｓ «ι↑Ｅ”o∨↙8”§ι±Ｉκ→

Try it online! Link is to verbose version of code. Only happened to read @Arnauld's answer after coding this but this is basically a port of it. Explanation:

Ｆ   «                   Loop over
  Ｓ                     Input string
 ⪪                       Split at spaces
     ι                  Print the word
        ”o∨↙8”          Compressed string 01120101
       Ｅ                Map over each character
                 Ｉκ     Cast character to integer
                ±       Negate
              §ι        Circularly index into word
      ↑                 Print array upwards, prints each element rightwards
                    →    Move right

Answer 8

sed, 46 bytes

s/^\(\(.\).*\(.\)\(.\)\)$/\1\2\4\4\3\2\4\2\4/g

Try it online!

Answer 9

JavaScript (ES6), 74 60 bytes

s=>s.map(s=>s+(a=s[l=s.length-1],b=s[0])+a+a+s[l-1]+b+a+b+a)

Takes input as an array, and outputs an array.

-9 bytes thanks to Programmer5000

Test cases:

let f=

s=>s.map(s=>s+(a=s[l=s.length-1],b=s[0])+a+a+s[l-1]+b+a+b+a)

console.log(JSON.stringify(f(['ellipsis']))) // ellipsisessieses
console.log(JSON.stringify(f(['goat']))) // goatgttagtgt
console.log(JSON.stringify(f(['covfefe']))) // covfefeceefcece
console.log(JSON.stringify(f(['programmer5000']))) // programmer5000p000p0p0
console.log(JSON.stringify(f(['up', 'vote', 'down', 'goat']))) // upuppuupup,voteveetveve,downdnnwdndn,goatgttagtgt
console.log(JSON.stringify(f(['it', 'is', 'golf', 'yo']))) // itittiitit,isissiisis,golfgfflgfgf,yoyooyyoyo
console.log(JSON.stringify(f(['crossed', 'out', '44', 'is', 'still', '44']))) // crossedcddecdcd,outottuotot,4444444444,isissiisis,stillslllslsl,4444444444

Answer 10

Mathematica, 89 bytes

((f[a_]:=#~StringTake~a;k=#<>(q=f@1)<>(w=f[-1])<>w<>f@{-2}<>q<>w<>q<>w)&/@StringSplit@#)&

Answer 11

Pyth, 17 bytes

Uses the same trick as in @Jonathan's answer.

m+dsm@dttkj5416 3

Try it here! or Check out the test Suite (Give it some time).

Port of my Python solution, 19 bytes 18 bytes:

m+dsm@d_k+0j1144 3

Answer 12

Dyalog APL, 51 49 bytes

Requires ⎕ML←3

∊{⍺,' ',⍵}/{S←1,L←≢⍵⋄⍵,⍵[∊S(L-0 1)S S]}¨' '(≠⊂⊢)⍞

-9 bytes thanks to @Adám in chat!

Try it online!

Answer 13

Paradoc (v0.2.10), 13? bytes (CP-1252)

µ96Qó3BÌDX=v+

Try it online!

Takes a list of words, and results in a list of words on the stack.

A small variation on the base-3 trick. Maybe it's time to work on my base 250-whatever compressor.

Explanation:

μ             .. Map the following block over each word (the block is
              .. terminated by }, but that doesn't exist, so until EOF)
              .. (The word is on the stack now.)
 96Qó         .. 96 * 26 (Q in base 26) = 2496, a hack to prevent us from
              .. needing a space to separate this from the following number.
     3B       .. Convert 2496 to base 3 to get [1,0,1,0,2,1,1,0]
       ÌD     .. Negate and reverse to get [0,-1,-1,-2,0,-1,0,-1]
         X    .. Push the loop variable: the word being mapped over
          =v  .. Index, vectorize; map over the indices by indexing them
              .. into the word
            + .. Concatenate with the original word

(Byte-counting question: Now that I'm actually demonstrating this in TIO, it take a list of words on the stack and results in a list of words on the stack, but you can't really do much with that list of words unless you close the block started by µ. Should I count that closing brace?)

Answer 14

Wolfram Language/Mathematica, 66 bytes

StringJoin[StringSplit[#,""]/.{a_,___,b_,c_}:>{#,a,c,c,b,a,c,a,c}]&

Just whipped it up real quick, might have a minor improvement here or there.

Answer 15

Perl 5, 55 49 + 1 (-a) = 56 50 bytes

used a trick from @Arrnauld's post to save a couple bytes

say map$_.'01120101 '=~s/\d/substr$_,-$&,1/egr,@F

Try it online!

Answer 16

Charcoal, 38 30 bytes

-8 bytes thanks to ASCII-only.

Ｆ⪪Ｓ «ι§ι⁰ײ§ι±¹§ι±²×²⁺§ι⁰§ι±¹ 

Try it online! Link is to verbose version.

Note the trailing space.

Answer 17

Java 8, 117 bytes

a->{int i=0,l;for(String s:a){char c=s.charAt(0),d=s.charAt(l=s.length()-1);a[i++]+=""+c+d+d+s.charAt(l-1)+c+d+c+d;}}

Takes the input as a String-array, and modified this original array instead of returning a new one to save bytes.

Can most likely be golfed some more..

Explanation:

Try it here.

a->{                          // Method with String-array as parameter and no return-type
  int i=0,                    //  Index-integer (starting at 0)
      l;                      //  Length-integer which we use multiple times
  for(String s:a){            //  Loop over the input array
    char c=s.charAt(0),       //   The first character of the word
         d=s.charAt(          //   The last character of the word
            l=s.length()-1);  //    and set `l` at the same time to `length()-1`
    a[i++]+=                  //   Append to the current value in the array:
      ""                      //    String so the characters aren't appended as integers
      +c                      //    + the first character
      +d+d                    //    + two times the last character
      +s.charAt(l-1)          //    + the single-last character
      +c+d+c+d;               //    + the first + last character two times
  }                           //  End of loop
}                             // End of method

Answer 18

C# (.NET Core), 106 bytes

n=>{for(int i=0,x;i<n.Length;){var h=n[i];x=h.Length-1;char y=h[0],j=h[x];n[i++]=h+y+j+j+h[x-1]+y+j+y+j;}}

Try it online!

Lambda function that takes input as array of strings, and modifies original array for output