function calc_price(){
	var size = {1:1050, 2:1680, 3:2310, 4:2940, 5:3570};
	var lining = [1, 1.5];
	var price = {}
	
	var charge = document.getElementsByName('charge');
	for (i=0; i<charge.length; i++) {
	    var select_pay = charge[i].checked ? 315 : 0;
    	document.form.pay.value = select_pay;
    }
	for (i=1; i<=5; i++) {
		var size_price = size[document.form["size" + i].selectedIndex + 1];
		var select_lining = lining[document.form["lining" + i].selectedIndex];
		
		price[i] = Math.floor(size_price * document.form["num_sheets" + i].selectedIndex * select_lining * 1);
		document.form["price" + i].value = price[i];
	}
	var total = price[1] + price[2] + price[3] + price[4] + price[5] + parseInt(document.form.carriage.value) + select_pay;
	
	document.form.total.value = total;
}