function calcular(form){
	var impressoes = document.getElementById('userInput').value;
	document.getElementById('livros').innerHTML = impressoes * 14;
	document.getElementById('entrega-correio').innerHTML = impressoes * 4;
	document.getElementById('entrega-sedex').innerHTML = impressoes * 14;

	for (var i = form.length - 1; i > -1; i--) {
		if (form[i].checked) {
			if (form[i].value == 0) {
				correios();
			}
			else if (form[i].value == 1) {
				sedex();
			}
			else if (form[i].value == 2) {
				editora();
			}
			else if (form[i].value == 3) {
				motoboy();
			}
			else if (form[i].value == 4) {
				autor();
			}
		}
	}
return false;
}

function correios(){
	document.formcompra.tipodeentrega[0].checked = true;
	var impressoes = document.getElementById('userInput').value;
	document.forms["formcompra"].elements["item_descr_2"].value = "Entrega via Correios";
	document.forms["formcompra"].elements["item_valor_2"].value = impressoes * 400;
	document.getElementById('total').innerHTML = (impressoes * 14) + (impressoes * 4) + ",00";
}

function sedex(){
	document.formcompra.tipodeentrega[1].checked = true;
	var impressoes = document.getElementById('userInput').value;
	document.forms["formcompra"].elements["item_descr_2"].value = "Entrega via SEDEX";
	document.forms["formcompra"].elements["item_valor_2"].value = impressoes * 1400;
	document.getElementById('total').innerHTML = (impressoes * 14) + (impressoes * 14) + ",00";
}

function editora(){
	document.formcompra.tipodeentrega[2].checked = true;
	var impressoes = document.getElementById('userInput').value;
	document.forms["formcompra"].elements["item_descr_2"].value = "Retirar na editora";
	document.forms["formcompra"].elements["item_valor_2"].value = 100;
	document.getElementById('total').innerHTML = (impressoes * 14) + (1) + ",00";
}

function motoboy(){
	document.formcompra.tipodeentrega[3].checked = true;
	var impressoes = document.getElementById('userInput').value;
	document.forms["formcompra"].elements["item_descr_2"].value = "Entrega via motoboy";
	document.forms["formcompra"].elements["item_valor_2"].value = 2000;
	document.getElementById('total').innerHTML = (impressoes * 14) + (20) + ",00";
}

function autor(){
	document.formcompra.tipodeentrega[4].checked = true;
	var impressoes = document.getElementById('userInput').value;
	document.forms["formcompra"].elements["item_descr_2"].value = "Entrega pelo proprio autor";
	document.forms["formcompra"].elements["item_valor_2"].value = 10000;
	document.getElementById('total').innerHTML = (impressoes * 14) + (100) + ",00";
}