function highlight(Olgs) {
    for (i=0; i < Olgs.length; i++){
        document.getElementById("court_"+Olgs[i]).style.backgroundColor = "lightYellow";
    }
}
function dim(Olgs) {
    for (i=0; i < Olgs.length; i++){
        document.getElementById("court_"+Olgs[i]).style.backgroundColor = "white";
    }
}