Adoro questo semplice codice, è così divertente leggere parole non abbastanza leggibili dall'uomo e colmare le lacune ...

Ot wes thi bist uf tomis, ot wes thi wurst uf tomis, 
ot wes thi egi uf wosdum, ot wes thi egi uf fuuloshniss, 
ot wes thi ipuch uf biloif, ot wes thi ipuch uf oncridaloty, 
ot wes thi siesun uf loght, ot wes thi siesun uf derkniss, 
ot wes thi sprong uf hupi, ot wes thi wontir uf dispeor, 
wi hed ivirythong bifuri as, wi hed nuthong bifuri as, 
wi wiri ell guong dorict tu hievin, wi wiri ell guong dorict thi uthir wey – 
on shurt, thi piroud wes su fer loki thi prisint piroud, 
thet sumi uf ots nuosoist eathurotois onsostid un ots biong riciovid, 
fur guud ur fur ivol, on thi sapirletovi digrii uf cumperosun unly.

Le regole sono semplicissime:

• Accetta del testo come input (caratteri ASCII, lettere maiuscole / minuscole e punteggiatura).
• Per ogni vocale, ruotala sulla vocale successiva o torna all'inizio.
  • a => e
  • e => i
  • i => o
  • o => u
  • u => a
• Le vocali maiuscole rimangono maiuscole, le vocali minuscole rimangono minuscole.
• Stampa il testo dopo queste conversioni.
• Non c'è bisogno di sostenere gli accenti.
• Tutti gli altri personaggi dovrebbero rimanere invariati.
• Prova a farlo nel minor numero di byte.
• Qualunque vecchia lingua che ti piace.

Casi test

It was the best of times, it was the worst of times,
it was the age of wisdom, it was the age of foolishness,
it was the epoch of belief, it was the epoch of incredulity,
it was the season of light, it was the season of darkness,
it was the spring of hope, it was the winter of despair,
we had everything before us, we had nothing before us,
we were all going direct to heaven, we were all going direct the other way –
in short, the period was so far like the present period,
that some of its noisiest authorities insisted on its being received,
for good or for evil, in the superlative degree of comparison only.

Su:

Ot wes thi bist uf tomis, ot wes thi wurst uf tomis, 
ot wes thi egi uf wosdum, ot wes thi egi uf fuuloshniss, 
ot wes thi ipuch uf biloif, ot wes thi ipuch uf oncridaloty, 
ot wes thi siesun uf loght, ot wes thi siesun uf derkniss, 
ot wes thi sprong uf hupi, ot wes thi wontir uf dispeor, 
wi hed ivirythong bifuri as, wi hed nuthong bifuri as, 
wi wiri ell guong dorict tu hievin, wi wiri ell guong dorict thi uthir wey – 
on shurt, thi piroud wes su fer loki thi prisint piroud, 
thet sumi uf ots nuosoist eathurotois onsostid un ots biong riciovid, 
fur guud ur fur ivol, on thi sapirletovi digrii uf cumperosun unly.

Nel:

The quick brown fox jumps over the lazy dog.

Su:

Thi qaock bruwn fux jamps uvir thi lezy dug.

Nel:

Home is where the heart is.

Su:

Humi os whiri thi hiert os.

Nel:

Boaty McBoatface

Su:

Buety McBuetfeci

Nel:

AEIOUaeiou

Su:

EIOUAeioua

Nel:

Programming Puzzles And Code Golf

Su:

Prugremmong Pazzlis End Cudi Gulf

Stax, 7 bytes

öΦΣòC└∞

Run and debug it

Try it online!

Explanation (unpacked)

Vv:tVV:t
Vv:t           #Push aeiou and ring translate it to input
    VV:t       #Push AEIOU and ring translate it to input

Might be able to save more, will keep trying.

MS-SQL, 51 Bytes

Works on SQL 2017 or above:

SELECT TRANSLATE(v,'AEIOUaeiou','EIOUAeioua')FROM t

The new function TRANSLATE performs individual character replacement, so is ideally suited for this challenge.

Input is via a pre-existing table t with varchar column v, per our IO rules.

In this case the table must be created using a case-sensitive collation, either by running on a case-sensitive server, or by using the COLLATE keyword (not counted toward character total):

CREATE TABLE t(v varchar(max) COLLATE Latin1_General_CS_AS)

EDIT: SSMS may cut off the lengthy quote above when returning the result in a "results to text" window, this is a client setting, not a bug in my program.

To fix, go to Tools > Options > Query Results > SQL Server > Results to Text and increase the "Maximum number of characters displayed in each column."

Bash + coreutils, 24

tr aeiouAEIOU eiouaEIOUA

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Haskell, 52 bytes

(a:b)!c|a/=c=b!c|1>0=b!!0
a!b=b
map("aeiouaAEIOUA"!)

Try it online!

Lynn saved me two bytes by pointing out that !!0 is shorter than head.

Explanation

If you have never coded in Haskell this will probably look like a pile of jibberish. So first let's ungolf it and then break it down:

(a:b)!c
 |   a/=c   = b!c
 |otherwise = b!!0
a!b=b
map("aeiouaAEIOUA"!)

First we have a function !, which takes a string s and a character c. Our first pattern match catches accepts input if the string is non-empty. If the string is non-empty we compare its first character to c. If it's first character is not equal to c we toss it and call ! again with the remainder of the string and c. If it is equal we return the second character in the string.

Our next pattern match catches the string in all other cases, that is if the string is empty. In this case we just return c.

All in all this function takes a character c and a string s and returns the character after the first occurrence of c in s. If we pass this with aeiouaAEIOUA it will perform our cipher on a single character. To make our whole function we ought to map this across the string.

Retina, 10 9 8 bytes

T`uo`vVA

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Saved 1 byte thanks to Neil! And another byte thanks to Martin!

The new version of retina has vowel classes, which makes the result a bit shorter. The transliteration also makes use of the "other" class. So the to class looks like "aeiouAEIOUA" while the from class looks like "uaeiouAEIOUA"

This doesn't cause any problems since the second u mapping to A will never be done since u was already mapped to a.

Perl 5 + -p, 24 23 bytes

y;AEIOUaeiou;EIOUAeioua

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-1 byte thanks to @DomHastings

Python 3, 62 bytes

lambda x:x.translate(str.maketrans('aeiouAEIOU','eiouaEIOUA'))

Make a translation table (dictionary) with str's static str.maketrans method. Translate relevant characters to their destination character.

C, 85 76 67 65 64 bytes

f(char*c){for(;*c;)putchar(1[index("AEIOUAaeioua",*c++)?:c-2]);}

Port of Kevin Cruijssen's Java answer. Try it online here.

Thanks to Kevin Cruijssen for golfing 9 bytes, to Christoph for golfing 11 bytes and to ceilingcat for golfing 1 byte.

Ungolfed version:

f(char* c) { // function taking a char array as parameter and implicitly returning an unused int
    for(; *c ;) // loop over the input
        putchar(1 [index("AEIOUAaeioua", * c++) ?: c-2]); // find the first pointer to the current char in the vowels string, NULL if not present; if it's not NULL, print the next vowel, otherwise just print the char
}

R, 43 bytes

chartr("AEIOUaeiou","EIOUAeioua",scan(,""))

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Here's my solution wrapped in a cat to get it to print out more nicely: Try it online!

Jelly, 11 bytes

Øcs5ṙ€-Ẏ,Ʋy

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Python 2, 79 68 67 bytes

-1 byte thanks to @ArnoldPalmer

V='uaeiouAEIOUA'
print''.join((V[1:]+c)[V.find(c)]for c in input())

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JavaScript (ES6), 60 bytes

s=>s.replace(/./g,c=>(S='aeiouaAEIOUA'+c+c)[S.indexOf(c)+1])

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Ruby -p, 31 bytes

$_.tr!"AEIOUaeiou","EIOUAeioua"

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Pyth, 17 bytes

em=.rQdrB"aeiou"1

Try it here

em=.rQdrB"aeiou"1
 m                  For each string...
       rB"aeiou"1   ... in ['aeiou', 'AEIOU']...
  =.rQd             ... cyclically rotate the characters in the input.
e                   Take the last.

Japt 2.0, 25 21 bytes

I had fun golfing this one with Shaggy.

r\v@=`aeia`pu)g1+UbX

Run it here.

Java 10, 97 87 bytes

s->{for(var c:s){var t="AEIOUAaeioua"+c+c;System.out.print(t.charAt(t.indexOf(c)+1));}}

-10 bytes after being inspired by @Arnauld's JavaScript answer (his 60-bytes version).

Try it online.

Explanation:

s->{                         // Method with character-array parameter and no return-type
  for(var c:s){              //  Loop over the input characters
    var t="AEIOUAaeioua"     //  Temp-String containing the order of vowels 
                             //  (including additional 'A' and 'a'),
          +c+c;              //  appended with two times the current character
    System.out.print(        //  Print:
      t.charAt(              //   The character in String `t` at index:
         t.indexOf(c)+1));}} //    The (first) index of the current character in `t` + 1

05AB1E, 14 13 11 bytes

žMDÀ‡žMuDÀ‡

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Retina 0.8.2, 20 bytes

T`_o`A\EI\OUAaei\oua

Try it online! Link includes test cases.

APL+WIN, 55 bytes

Prompts for input string:

i←(10≥n←'AEIOUaeiou'⍳s)/⍳⍴s←⎕⋄s[i]←'EIOUAeioua'[n~11]⋄s

Mumps, 38 bytes

R T W $TR(T,"AEIOUaeiou","EIOUAeioua")

Mumps doesn't normally add a carriage return, as I didn't see a requirement to separate input from output it does look a bit weird on first run. For example, the output for the last test case looks like this:

Programming Puzzles And Code GolfPrugremmong Pazzlis End Cudi Gulf

If you did want to add a carriage return, add two bytes thusly:

R T W !,$TR(T,"AEIOUaeiou","EIOUAeioua")

Vim + tpope/vim-abolish, 30 bytes

:%S/{a,e,i,o,u}/{e,i,o,u,a}/g<cr>

Alternate solution, also 30 bytes:

Oe,i,o,u<esc>|D:%s/{a,<C-r>"}/{<C-r>",a}/g

According to meta, vim answers can use plugins with no byte penalty. This is not a vim answer, but a vim + abolish answer.

Abolish is an extremely useful plugin. This section of the README nicely describes how this command (the Subvert command) works.

CJam, 29 19 bytes

q"aeioua"_eu+_1m<er

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-10 bytes thanks to @Peter Taylor

Explanation:

q                       # take all input
 "aeioua"               # push vowel pairs
         _eu            # duplicate, uppercase
            +_          # concatenate, duplicate again
              1m<       # rotate left by 1
                 er     # transliterate

AutoHotkey, 24 bytes

AuotHotkey automatically replaces letters in a case sensitive manner.

a::e
e::i
i::o
o::u
u::a

PHP, 90 Bytes

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Code

function f($s){echo strtr($s,array_combine(str_split(UuAaEeIiOo),str_split(AaEeIiOoUu)));}

Explanation

function f($s){
 echo strtr(
       $s,                          #The string to operate
       array_combine(               #combining arrays
            str_split(UuAaEeIiOo),  #splitting this strings
            str_split(AaEeIiOoUu))
              # With array combine php creates an array like
              # ["U"=>"A", "a"=>"e"....and so on]
              # strtr can replace strings in a string, using an array with 
              # the values to replace and with what replace each value.
 );
}

75 Bytes if ran with php -r using $argv

<?=strtr($argv,array_combine(str_split(UuAaEeIiOo),str_split(AaEeIiOoUu)));

J, 33 bytes

rplc'aeiou',&((;"0)1&|.)'AEIOU'"1

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str, 18 bytes

[aeiouaAEIOUA]#D#U

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Explanation

                       implicit: over each character of the input:
[aeiouaAEIOUA]#D#U
[            ]         push this string
              #D       set this to the operation domain
                #U     set the charcter to the next character in the domain

PHP, 38 bytes

Quite simple, not very creative, uses strtr to replace the vowels:

<?=strtr($argn,aeiouAEIOU,eiouaEIOUA);

Run with echo '<input>' | php -nF <filename> or Try it online.

q/kdb+, 36 33 bytes

Solution:

{(v,2#x)1+(v:"aeiouaAEIOUA")?x}@'

Examples:

q){(v,2#x)1+(v:"aeiouaAEIOUA")?x}@'"AEIOUaeiou"
"EIOUAeioua
q){(v,2#x)1+(v:"aeiouaAEIOUA")?x}@'"Programming Puzzles And Code Golf"
"Prugremmong Pazzlis End Cudi Gulf"

Explanation:

Figure out index of vowels, add one to push along to the next and index in. Still think this approach can be significantly improved...

{(v,2#x)1+(v:"aeiouaAEIOUA")?x}@' / the solution
{                             }@' / apply lambda to each character of input
                            ?x    / look up x in...
          (                )      / do together
             "aeiouaAEIOUA"       / lookup list
           v:                     / save as v
        1+                        / add one
 (     )                          / do together
    2#x                           / take 2 copies of x
  v,                              / prepend v

Bonus:

My old **36 byte(()) solution which I think is quite cool, but need to golf down the lists to make it competetive:

ssr/[;"uoiea%UOIEA%";"%uoiea%UOIEA"]

Charcoal, 35 bytes

ＵＴ≔AUOIEAauoieaσＦ¹¹⊞υ➙§σ⊕ι§σι▷SR⟦Ｓυ

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Naive method.

Explanation:

ＵＴ                                         Set trim option to on, so output won't be a rectangle
    ≔AUOIEAauoieaσ                          Assign "AUIOEAauioea" to s
                   Ｆ¹¹                      For i (ι) from 0 to 10
                       ⊞υ                   Push to u (initially empty list)
                          ➙                 Rule of:
                            §σ⊕ι            S[i + 1]
                                 §σι         to S[i]. This is so a->A gets overwriteen by a->e
                                    ▷SR⟦Ｓυ  Replace input as string using u (now a list of rules)

PHP, 76 bytes.

$s=strtr($s,array_combine(str_split("aeiouAEIOU"),str_split("eiouaEIOUA")));

Check it out!

This was the shortest I was able to do this in PHP.

$s = //overwrite $s variable ($s should be a defined string or input)
    strtr(  //strtr replaces key => value pairs from arrays in a string
        $s, //the string we are converting
        array_combine( //create an array with key value pairs, key should be original vowel letter and value should be it's replacement
            str_split("aeiouAEIOU") //turn vowels (lower and upper) into an array
            ,str_split("eiouaEIOUA") //turn vowel replacements into an array
        )
    );