function set_page(pagenum){
  document.getElementById('p').value = pagenum;
  document.getElementById('s_form').submit();
}
function clear_search(){
  document.getElementById('p').value = 0;
  document.getElementById('s_param').value = '';
  document.getElementById('s_form').submit();
}
function add_item(id){
  document.getElementById('product_id').value = id;
  document.getElementById('product_count').value = document.getElementById('product_count_'+id).value;
  document.getElementById('s_form').submit();
}