function calculate()
{
	if(document.getElementById("dc2").value=="")
	{
			alert("Tolong inputkan hari pertama haid terakhir");
			document.getElementById("dc").focus();
			return false;
	}

one_day = 86400000;
date1=document.getElementById('dc').value.split('-');
date2=document.getElementById('dc2').value.split('-');
		birth = (Date.parse(date2[1]+" "+date2[0]+","+date2[2]) + (280*one_day));
		p_k=  new Date(birth);
		u_k=Math.floor((Date.parse(date1[1]+" "+date1[0]+","+date1[2]) - Date.parse(date2[1]+" "+date2[0]+","+date2[2])) / (7*one_day));
		strp_k=p_k.toLocaleString();
		strp_k=strp_k.replace("12:00:00","");
		strp_k=strp_k.replace("00:00:00","");
		strp_k=strp_k.replace("AM","");
		strp_k=strp_k.replace("PM","");
		document.getElementById("icon").bgColor="#74B71B";
		document.getElementById("hasil").innerHTML='<b><font color="#737373" size="2">Result</font></b>';
		document.getElementById("hasil").bgColor="#FFFFFF";
		document.getElementById("born").innerHTML="<font class=inputtext>Perkiraan Kelahiran : "+strp_k;

		document.getElementById("preg").innerHTML=" <font class=inputtext>Usia Kandungan : "+u_k+" weeks";
	
}