CodingForums.com - Display Results for Push & Pop Values

I have checked the forum and there are similar threads, but nothing that deals exactly with my issue.
I have 2 Arrays and a variable. I need to push an item onto the variable, and then with a second click push it onto Array 1. Then with i click a second button, the item in the varible is push onto Array 2, and the item in Array 1 is Poped onto the Variable.

Here is the code i have come up with, but i cannot pop the item from the Variable onto Array 2.

Any ideas:

<HTML>

<HEAD>

<TITLE>Stacking up!</TITLE>

<SCRIPT>







// 'txtPop.value = popBackStack();showStack(theList);pushForStack(txtPop.value);



// 'PushForStack(txtPop.value);txtPush.value"";txtPop.value = popBackStack();showStack(theList);showStack2(theList2);'





var backStack = new Array(); 

var forStack = new Array();

var curUrl = document.getElementById("txtPop");



function pushStack(newVal) {

   backStack.push(curUrl);

   curUrl = newVal;

}



function pushForStack(newVal) {

	CurUrl = newVal;

	forstack.push(curUrl);

}



function popBackStack() {

   var popVal = backStack.pop();  

   if (popVal == undefined)

      return "Nothing left!";

   else

   return popVal

}



function popForStack() {

   var popVal = forStack.pop();

   if (popVal == undefined)

      return "Enter a new URL";

   else

   return popVal;

}



function showStack(theSelect){

   theSelect.options.length = 0;

   for (var i = 0; i < backStack.length; i++){

      var theOption = new Option(backStack[i]);

      theSelect.options[theSelect.options.length] = theOption;

   }

}



function showStack2(theSelect){

   theSelect.options.length = 0;

   for (var i = 0; i < forStack.length; i++){

      var theOption = new Option(forStack[i]);

      theSelect.options[theSelect.options.length] = theOption;

   }

}

</SCRIPT>







</HEAD>

<BODY>

<FORM>

<table width="104%" height="364" border="5" cellpadding="3" cellspacing="3">

  <tr>

    <th width="30%" height="78" scope="col"><p>

    <INPUT type=button value="Back" onClick='txtPop.value = popBackStack();showStack(theList);pushForStack(curUrl);

    showStack2(theList2);'></p></th>

    <th width="46%" scope="col"><p>

  <center>

  <INPUT type=text name=txtPush>

  <INPUT type=button value="Push" onClick='pushStack(txtPush.value);txtPush.value="";txtPop.value = curUrl; showStack(theList);'>

  </center>

  </p></th>

    <th width="24%" scope="col"><p><INPUT type=button value="Forward" onClick="txtPop.value = popBackStack();showStack2(theList2);"></p></th>

  </tr>

  <tr>

    <td><p><center>

    <SELECT name="theList" size=12>

    </SELECT>

    </center></p></td>

    <td><p><center><INPUT type=textki name=txtPop size=25></center></p></td>

    <td><center>

    <SELECT name="theList2" size=12>

    </SELECT>

    </center></td>

  </tr>

</table>

</FORM>

<p>&nbsp;</p>

</BODY>

</HTML>