// JavaScript Document
var dge=document.getElementById;
function cl_expcol(a){
  if(!dge)return;
    document.getElementById(a).style.display = 
      (document.getElementById(a).style.display=='none')?
      'block':'none';
}
function cl_colall(){
  if(!dge)return;
  for(i=1;document.getElementById('ex'+i);i++){
    document.getElementById('ex'+i).style.display='none';
  }
}
window.onload = function()
  {
    cl_colall();
  }