menu_status = new Array();

function detect(theid) {
         if(document.getElementById(theid)) {
           return true;
         }
         else {
           return false;
         }
}
function show(theid) {
         if(detect(theid) == true) {
            var switch_id = document.getElementById(theid);

            if(menu_status[theid] != 'show') {
                switch_id.className = 'show';
                menu_status[theid] = 'show';
            }
         }
}
function hide(theid) {
         if(detect(theid) == true) {
           var switch_id = document.getElementById(theid);
           
           if(menu_status[theid] != 'hide') {
             switch_id.className = 'hide';
             menu_status = 'hide';
           }
         }
}
function chk_status(currentid,otherid) {
         if((detect(currentid) == true) || (detect(otherid) == true)) {
           if(menu_status[otherid] != 'hide')  {
             hide(otherid);
             show(currentid);
           }
           else {
             show(currentid);
           }
         }
}