var subs=new Array('sub1','sub2','sub3','sub4','sub5','sub6','sub7');
  function hideall() {
    for(x=0; x<subs.length;x++) {
      document.getElementById(subs[x]).style.visibility='hidden';
    }
  }

  function display(mode,ele) {
    if(mode=='s') {
      hideall();
      document.getElementById(ele).style.visibility='visible';
    }else {
      document.getElementById(ele).style.visibility='hidden';
    }
  }