Suppose that i have a word "FadTheChad" (or any word that has vowels) and want the vowels replaced with "*" and return all the possibilities (subsets? not sure how i could describe it) of the word in an array.

I tried using String.replace() on the whole string which gave me F*dTh*Ch*d. Then i tried looping over the string and doing .replace() again which returned F*dTheChad, FadTh*Chad, FadTheCh*d.

is there anyway that i could get something like

[
  'F*dTh*Ch*d',
  'F*dTheChad',
  'F*dTh*Chad',
  'F*dTheCh*d',
  'FadTh*Chad',
  'FadTh*Ch*d',
  'FadTheCh*d'
]

CodePudding user response：

Try this:

function getPossibilities(word) {
    let vowels = ['a', 'e', 'i', 'o', 'u']; // 'y'?
    let positions = [];
    for (let i = 0; i < word.length; i  ) {
        if (vowels.indexOf(word[i]) !== -1) positions.push(i);
    }
    let result = [], count = 2 ** positions.length;
    for (let i = 0; i < count; i  ) {
        let newWord = [...word];
        for (let j = 0; j < positions.length; j  ) {
            if ((i >> j) & 1) newWord[positions[j]] = '*';
        }
        result.push(newWord.join(''));
    }
    return result;
}

I make the word into an array because in JS strings are immutable so I wouldn't be able to modify indices like this.

CodePudding user response：

So the question is to find the vowels, then to find all possible combinations by replacing them with star.. pretty nice so here's my attempt

function vowelOptions(text,replacer){
  let isVowel={a:1,e:1,i:1,o:1,u:1}
  let vowels=[], toReturn=[]
  let data=text.split('')
  data.forEach((letter,i)=>{
    if(isVowel[letter]){vowels.push(i)} //location of vowel stored
  })
  for(let i=1;i<Math.pow(2,vowels.length);i  ){
    //Math.pow(2,vowels.length) are the number of vowel possibilities
    //i=1 and NOT 0 because default text is now allowed in return
    let dataOption=[...data] //a clone with a possible combination
    let combination=i.toString(2).split('').reverse() //the ones that will be '1' tell me where to put the replacer
    combination.forEach((bool,j)=>{
      if(bool=='1'){dataOption[vowels[j]]=replacer} //vowels to replace in this combination replaced thanks to vowel locations saved above
    })
    toReturn.push(dataOption.join(''))
  }
  return toReturn
}

//now watch it work >:}
console.log(vowelOptions("FadTheChad","*"))

<iframe name="sif1" sandbox="allow-forms allow-modals allow-scripts" frameborder="0"></iframe>

CodePudding user response：

A simple recursion makes this easy:

const addVowels = (str) => 
  str .indexOf ('*') < 0 
    ? str 
    : ['a', 'e', 'i', 'o', 'u'] .flatMap (v => addVowels (str .replace ('*', v)))

console .log (addVowels ('F*dTh*Ch*d'))

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<iframe name="sif2" sandbox="allow-forms allow-modals allow-scripts" frameborder="0"></iframe>

If our string contains no asterisks, we are done and simply return it.

If it has an asterisk, flatMapping the results of replacing that with each of the vowels and recurring on the resulting string.

---

For next time, please include some sample code for what you've tried.

CodePudding user response：

I am way too late, but maybe this is still of interest so someone?

const str="didadumdidum",v=[],
      parts=str.replace(/[aeiou]/gi,
    m=>(v.push(m),"*")).split("*"),
      n=1<<v.length;
  
for (let i=0; i<n; i  ) {
  let s=i.toString(2)
     .padStart(v.length,"0")
  console.log(
 parts.map((p,j)=>(j--? s[j]?v[j]:"*":"") p).join("")
)
}

<iframe name="sif3" sandbox="allow-forms allow-modals allow-scripts" frameborder="0"></iframe>

In my approach I used String.prototype.replace() with a callback function to collect the vowels in an array while splitting the string into an array (parts). The rest is similar to @thebombsquad's approach.