var last_number = 0;

function changeClass(id, classname) {
	document.getElementById(id).className=classname;
}

function changeClassOpen(number) {
	if(last_number == 0) {
		last_number = number;
	} else {
		changeClassClose(window.last_number)
		last_number = number;
	}
    changeClass('td'+ number, 'box_cal3_hover');
    changeClass('s'+ number, 'span_on');
}

function changeClassClose(number) {
    changeClass('d'+ number, 'datebox2');
    changeClass('td'+ number, 'box_cal3');
    changeClass('s'+ number, 'span_off');
}

function changeClassOver(number) {
    changeClass('d'+ number, 'datebox2_hover');
}

function changeClassOut(number) {
    changeClass('d'+ number, 'datebox2');
}