function changecss(obj)
{
for(i=1;i<10;i++)
{
if(document.getElementById("tab"+[i]))
{
document.getElementById("tab"+[i]).className=''
}
else
{
document.getElementById(obj).className='active'
}
}
}

function showmenu(tab)
{
i=1
while(document.getElementById("div"+i))
{
document.getElementById("div"+i).style.display='none'
i++
}
document.getElementById(tab).style.display='block'
}