Unique Items in output value using Jquery

I have attached below my code, in this code pending user i will get all pending users email id one by one froim sharepoint list item,but sometime i have repeated output .so i dont want to send email to repeated users. how to restrict the repaeted value here,

 

ex i have pending users name like,[email protected],[email protected],naveen@gmail .com,[email protected]. But i want to use name only one time. 

completefunc: function (xData, Status) {

 

$(xData.responseXML).SPFilterNode("z:row").each(function() {

Pendinguser = $(this).attr("ows_Vice_x002d_President");