Here we will take ROT13 encoded string as input and returns a decoded string.
//Caesars Cipher using javascript arrow functions
function rot13(str) {
return str.replace(/[A-Z]/g, L => String.fromCharCode((L.charCodeAt(0) % 26) + 65));
}
console.log(rot13("Gur dhvpx oebja sbk whzcf bire 13 ynml qbtf."));
console.log(rot13("LYrneavat jvgu Znawrrg"));