Codewar challenge

function toCamelCase(str){
  let splittingWord = str.split(/-|_/);
  
  let camelCaseString = "";
  
  for(let i = 0; i < splittingWord.length; i++){
    const upperLetters = splittingWord[i].toUpperCase()[0];
    const lowerLetters =  splittingWord[i].slice(1).toLowerCase();
        
     if (i === 0) {
      camelCaseString += upperLetters + lowerLetters;
    } else {
      camelCaseString += splittingWord[i].toUpperCase()[0]+lowerLetters;
    }
   
}
  console.log(camelCaseString);

}
toCamelCase("the-stealth-warrior");