Free Code Camp Bonfire: Mutations

FCCBonfire.js

function mutation(arr) {
  firstWord = arr[0].toLowerCase();
  secondWord = arr[1].toLowerCase().slice('');
  lettersFound = 0;
  for(i=0; i<secondWord.length; i++){
    indexSearch = secondWord[i];
    indexSearchResult = firstWord.indexOf(indexSearch, 0);
    if(indexSearchResult == -1) {
       return false;
       } else {
       lettersFound++;
       }
     
  }
  if (lettersFound>0) {
      return true;
    }
}

mutation(["hello", "hey"]);