function zegar()
{
    D = new Date();
    D.setTime(D.getTime());
    G = D.getHours();
    M = D.getMinutes(); M=M<10?'0'+M:M;
    S = D.getSeconds(); S=S<10?'0'+S:S;


    document.getElementById('zegar').innerHTML=' '+ G + ':' + M + ':' + S;
    setTimeout('zegar()', 1000);
}