function trim(s)
{
     ns = new String(s);
     while (ns.substring(0,1) == ' ') {
          ns = ns.substring(1,ns.length);
     }
     while (ns.substring(ns.length-1,ns.length) == ' ') {
          ns = ns.substring(0,ns.length-1);
     }
     return ns;
}