function display(id) 
{
	var category = document.getElementById(id);

	for (var i = 1; i<=10; i++) 
	{
		if (document.getElementById('category_'+i)) 
		{
			document.getElementById('category_'+i).style.display='none';
		}
	}
		
	if (category) 
		{
			category.style.display='block';
		}
}

function display_subcategory(id)
{
	var subcategory = document.getElementById(id);
	
	for (var j = 1; j<=10; j++)
	{
			
		if (document.getElementById('subcategory_'+j))
		{
			document.getElementById('subcategory_'+j).style.display='none';
		}
	}
	
	if (subcategory)
	{
		if (subcategory)
		{
			subcategory.style.display='block';
		}
	}
}