function address(x){
   var c='address'
   var a=x.city.options[x.city.options.selectedIndex].value
   var city=a!=''?'-c'+a:''
   var b=x.category.options[x.category.options.selectedIndex].value
   var category=b!=''?'-t'+b:''
   if(city!=''||category!='')location='address'+city+category+'.html'
   return false
}