JavaScript求最大数最小数

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<html>
<head lang="en">
<meta charset="UTF-8">
<title>倒计时--密码复杂度--最大最小数</title>
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<body>


<input type="text" +arrData1[0]);
}
function num(a,b){//若a<b,则a在b之前
return a-b;
}

</script>

</body>
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