为什么编译不出东西啊，帮我看看，哪里出错了啊？？？
小弟初来学习！遇到困难希望能指点指点<html>
<head>
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// -->
function makeArray(n)
{
this.length=n
return this
}
function hexfromdec(num)
{
hex=new makeArray(1);
var hexstring="";
var shifthex=16;
var temp1=num;
for(x=1;x>=0;x--)
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hex[x]=Math.round(temp1/shifthex-.5);
hex[x-1]=temp1-hex[x]*shifthex;
temp1=hex[x-1];
shifthex/=16;
}
for(x=1;x>=0;x--)
{
hexstring+=getletter(hex[x]);
}
return(hexstring);
}
function getletter(num)
{
if(num<10){return num;}
else
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if(num==10){return"A"}
if(num==11){return"B"}
if(num==12){return"C"}
if(num==13){return"D"}
if(num==14){return"E"}
if(num==15){return"F"}
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}
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allstring+="<FONT COLOR="+color_h1+"ff"+color_h1+">"+text.substring(i,i+2)+"</FONT>";
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return allstring;
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function sizefont(text)
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var allstring="";
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allstring+="<FONT SIZE="+J+">"+text.substring(i,i+1)+"</FONT>";
}
return allstring;
}
document.write("<font size=8><CENTER>")
document.write("<br><br>")
document.write(sizefont("这是一个获取WEB浏览器的程序"))
document.write("</CENTER></font>")
document.write("浏览器名称:"+navigator.appName+"<br>");
document.write("版本号："+navigator.appVersion+"<br>");
document.write("代码名字："+navigator.appCodeName+"<br>");
document.write("用户代理标识:"+navigator.userAgent);
</script>
<body>
</body>
</head>
</html>
帮帮忙改改
