menambahkan function

<html>
<head>
<title>menambahkan function</title>
<script language ="javascript">

var stack = new Array();

function input_ke_stack(data)
{
stack.push(data);
}


function ambil_dari_stack()
{
var data_dari_stack = stack.pop();
if (data_dari_stack == undefined)
return "Stack sudah Kosong";
else
return data_dari_stack;
}


function tampilkan_stack(list)
{
list.options.length = 0;
for (var i=0; i<stack.length; i++)
{
var data = new Option(stack[i]);
list.options[list.options.length] = data;
}
}

</script>
</head>
<body>
<form>

<input type=text name=textsimpan>

<input type=button value="Masukkan Ke Stack"
onClick='input_ke_stack(textsimpan.value);
textsimpan.value="";
tampilkan_stack(mediaList);'>

<select name="mediaList" size=12>
<option>Tampilkan Data...
</select>

<input type=text name=textambil size=20>
<input type=button value="Ambil Dari Stack"
onClick='textambil.value=ambil_dari_stack();
tampilkan_stack(mediaList);'>

</form>
</body>
</html>