function zobrazit() {
    let text = document.getElementById("gettext").value;

    document.getElementById("logsystem").innerHTML += "<li>"+text+"</li>";
}

function updatename() {
    let fn = document.getElementById("firstname").value;
    let ln = document.getElementById("lastname").value;

    document.getElementById("getfn").innerHTML = fn;
    document.getElementById("getln").innerHTML = ln;
}

function sectihodnoty(x,y) {
    var z = x.toString()+y.toString();
    console.log("x+y=z -->  "+x+"+"+y+"="+z);
}