function display_subcategory_div(sid){
  var id ='sidenav_subcategory_'+sid;
	var myDiv = document.getElementById(id);
	if(myDiv.style.display=='none' || myDiv.style.display==''){
	  myDiv.style.display='block';
	}
	
	for(i=1;i<21;i++){
	  if(sid!=i){
		  var divId ='sidenav_subcategory_'+i;
			if(document.getElementById(divId)){
			  document.getElementById(divId).style.display='none';
			}
		}
	}
}   

function hide_all_subcategories()
{
  for(i=1;i<21;i++){
		var divId ='sidenav_subcategory_'+i;
	  if(document.getElementById(divId)){
			document.getElementById(divId).style.display='none';
		}
	}
}