function encodeAndDecodeMessages() {

    function ascii(a) { return a.charCodeAt(0); }

    encodeBtn = document.querySelector("#main > div:nth-child(1) > button");

    dencodeBtn = document.querySelector("#main > div:nth-child(2) > button");

    encodeBtn.addEventListener('click', encodeMessages);

    dencodeBtn.addEventListener('click', decodeMessages);

    function encodeMessages() {

        let theText = document.querySelector("#main > div:nth-child(1) > textarea").value;

        let encodedMessage = '';


        for (let i = 0; i < theText.length; i++) {

          encodedMessage += String.fromCharCode(ascii(`${theText[i]}`) + 1);
        }

        document.querySelector("#main > div:nth-child(1) > textarea").value="";

        document.querySelector("#main > div:nth-child(2) > textarea").value = encodedMessage ;

    }


    function decodeMessages() {

        let theText = document.querySelector("#main > div:nth-child(2) > textarea").value;


        let decodedMessage = '';

        for (let i = 0; i < theText.length; i++) {

            decodedMessage += String.fromCharCode(ascii(`${theText[i]}`) - 1);
        }

        document.querySelector("#main > div:nth-child(2) > textarea").value = decodedMessage ;
    }
}