Example, input:

aasddeeeaa

Result:

AaSDdEeeAa

I split the string into an array of letters, then have to check if the letter is occurred again after

CodePudding user response：

this way

const Cap1stR = s => [...s].reduce((r,c,i,{[i-1]:p})=>(r =(p===c)?c:c.toUpperCase(),r),'')


console.log( Cap1stR('aasddeeeaa') )

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CodePudding user response：

Here is a lazy solution to your problem (It works but it is ugly as hell).

let oldString = "aasddeeeaa"
let newString = ""
for(let charNb =1;charNb < oldString.length-1; charNb  ){
let char = oldString[charNb]
let previousChar = oldString[charNb-1]
if(char === previousChar){
newString  = char
}
if(char !== previousChar){
newString  = char.toUpperCase()
}
}
console.log(newString)

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You should use regex for this kind of problem but this will probably be good enough. I hope this is what you needed.

CodePudding user response：

const values = "aasddeeeaa"

let str = ""
let letter = 0;
for (let data of values.split("")) {
  if (letter == 0) {
    str  = data.toUpperCase();
  } else {
    let prev = values.split("")[letter - 1];
    if (data.toLowerCase() != prev.toLowerCase()) {
      str  = data.toUpperCase()
    } else {
      str  = data.toLowerCase()
    }

  }
  letter  ;
}

console.log("Answere =>", str)

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