document.getElementById("d0").style.display = "block";
document.getElementById("f0").className = "f_num_s"
function showFNum(s) {
    for(i=0;i<5;i++) {
        try{
        document.getElementById("d"+i).style.display = "none";
        document.getElementById("f"+i).className = "f_num"
        }catch(e){}
    }
    try{
    document.getElementById("d"+s).style.display = "block";
    document.getElementById("f"+s).className = "f_num_s"
    }catch(e){}
}