var unitCnt = 30;
var loc = window.location.href;
var pos = loc.indexOf(".html");	
var curUnit = loc.substr(loc.lastIndexOf("/")-2,2);
var currentStep = loc.substr(pos-1,1)-0;
/*dropdown selection*/
function writeSelect()
{
	document.write("<option value=\"../index.html\">トップページに戻る</option>");
	for (var i=1;i<=unitCnt;i++)
	{
		if (i == curUnit)
		{
			document.write("<option value=\"../lesson" + curUnit +"/2.html\" selected>第 " + i +" 課</option>");
		}
		else
		{
			var tStr = "a000" + i;
			tStr = tStr.substr(tStr.length - 2,2);
			document.write("<option value=\"../lesson" + tStr +"/2.html\">第 " + i +" 課</option>");
		}
	}
}

function writeheader() {
	var s='<iframe src="http://japanese.cri.cn/include/head980.htm" width="980" height="93" frameborder="0" scrolling="no"></iframe>';
	document.getElementById("header").innerHTML=s;
	s='<iframe src="http://japanese.cri.cn/include/foot980.htm" width="980" height="102" frameborder="0" scrolling="no"></iframe>';
	document.getElementById("footer").innerHTML=s;
}

window.onload=writeheader;