menu by default should hidden

menu by default should hidden

Hey guys i want the sensor to be hidden by default and it show when i
click on the particular node..and should be the same on page reload Here
is my code
<ul >
<?php if(isset($nodes)): ?>
<?php $count = 0; ?>
<?php foreach($nodes as $node) { ?>
<?php $node_id=$node['node_id']; ?>
<?php $sensors = config_sensor_model::getsensors($node_id); ?>
<?php $count++; ?>
<li onclick="menu(<?php echo $count; ?>)"><a href="#"><?php echo
$node['node_name']; ?> </a></li>
<ul id="<?php echo "sub_".$count; ?>">
<?php foreach($sensors as $sensorlog) { ?>
<li><a href="<?php echo site_url();
?>/dashboard/dashboard_graph/?node=<?php echo $node['node_id'];
?>&sensor=<?php echo $sensorlog->sensor_index;
?>&range=0&xticker=2&plot_graphs_value=1">&nbsp;&nbsp;&nbsp;&nbsp;<?php
echo $sensorlog->sensor_name; ?></a></li>
<?php } ?>
</ul>
<?php } ?>
<?php endif; ?>
</ul>
</div>
this is the javascript presently i am using
<script
src="http://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js">
</script>
<script>
function menu(count)
{
$("#sub_"+count).toggle("fast");
}
</script>