function showHideBlock()
{
  var numericID = this.id.replace(/[^\d]/g,'');
  var obj = document.getElementById('a' + numericID);
  hideAll();
  obj.style.display='block';
  /*
  if(obj.style.display=='block'){
  obj.style.display='none';
  }else{
  obj.style.display='block';
  }*/
}
function hideAll()
{
  var divs = document.getElementsByTagName('DIV');
  for(var no=0;no<divs.length;no++){
    if(divs[no].className=='hideblock'){
      divs[no].style.display='none';
    }

  }
}

function initShowHideContent()
{
  hideAll();
  var divs = document.getElementsByTagName('LI');
  for(var no=0;no<divs.length;no++){
    if(divs[no].className=='showblock'){
      divs[no].onclick = showHideBlock;
    }
  }
  var obj = document.getElementById('a1');
  obj.style.display='block';
}

window.onload = initShowHideContent;