<xhtml>
  <head>
    <title>Fibonacci number</title>
  </head>
  <body onload="alert(fib(10))">
    <script type="text/javascript"><![CDATA[
function fib(n) {
  var a = 1, b = 1;
  var tmp;
  while (--n >= 0) {
    tmp = a;
    a += b;
    b = tmp;
  }
  return a;
}
]]>
    </script>
  </body>
</xhtml>