My little work: Display in list box dynamically according to Drop-down list, and implement 2 list box mutually exclusive selection

Specific functions to know, in the dropdown box to select a, the left of the list box to display the corresponding value, point that 4 buttons to achieve left and right 2 list box options mutually exclusive, very fun. It is estimated that when we develop, we often need to use it, so we have to post it.
The code is as follows:
<style>
TD,SELECT,INPUT{FONT-SIZE:9PT}
</style>
<script>
var subcat = new Array (); Drop-down list Array definition
Subcat[0] = new Array ("plan buyer B", "2", "cs101");
SUBCAT[1] = new Array ("warehouse manager B", "2", "cs111");
SUBCAT[2] = new Array ("Warehouse manager", "1", "111");
SUBCAT[3] = new Array ("Store Manager", "1", "122");
SUBCAT[4] = new Array ("program Approver", "1", "MASTER");
SUBCAT[5] = new Array ("plan approver B", "2", "cs100");
SUBCAT[6] = new Array ("Plan Buyer", "1", "103");
SUBCAT[7] = new Array ("Statistician", "1", "Li Shangying");
SUBCAT[8] = new Array ("Statistician B", "2", "cs133");
This array can continue to add elements according to the actual needs of the program
var onecount=subcat.length;
var c=0;d=0; Index position of the optoins of the 2 select ...
function Moveto2 (FN,S1,S2)//">>" button function