text: function toChar13(charCo)
  {
    if(65 <= charCo && charCo <= 90)
    {
        return (90 - charCo >= 13) ? String.fromCharCode(charCo + 13)
        : String.fromCharCode(65 +  12 - (90 - charCo)) ; 
    }
    else { return String.fromCharCode(charCo); }
    
  }
  function rot13(str) {
    let strArrayzed = str.split("")
    strArrayzed.forEach( (item, index) => strArrayzed[index] = item.charCodeAt(0))
    strArrayzed.forEach( (code, index) => strArrayzed[index] = toChar13(code))
  
    console.log(strArrayzed.join(""));
    return strArrayzed.join("");
  }
  // 65-90
  rot13("SERR PBQR PNZC");
  