Struktur Data Stack

?html?
?head?
?title?Struktur Data Stack?/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 TampilkanStack (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 = "";
TampilkanStack (mediaList);'?

?select name = "mediaList" size = 12?
?option?Tampilan Data . . .
?/select?
?input type = text name = textAmbil size = 20?
?input type = button value = "Ambil dari Stack"
onClick = "textAmbil.value = Ambil_dari_Stack ();
TampilkanStack (mediaList);"?
?/form?
?/body?
?/html?