var jqueryslidemenu={
  
  animateduration: {over: 200, out: 100}, //duration of slide in/ out animation, in milliseconds
  
  buildmenu:function(menuid){
      jQuery(document).ready(function($){
          var $mainmenu=$("#"+menuid+">ul")
          var $headers=$mainmenu.find("ul").parent()
          $headers.each(function(i){
              var $curobj=$(this)
              var $subul=$(this).find('ul:eq(0)')
              this._dimensions={w:this.offsetWidth, h:this.offsetHeight, subulw:$subul.outerWidth(), subulh:$subul.outerHeight()}
              this.istopheader=$curobj.parents("ul").length==1? true : false
              $subul.css({top:this.istopheader? this._dimensions.h+0+"px" : 0})
              
              $curobj.mouseover(
                  function(e){
                      var $parent = $(this);
                      $parent.addClass("select");
                  }
              )
              $curobj.mouseout(
                  function(e){
                      var $parent = $(this);
                      $parent.removeClass("select");
                  }
              )
              
              $curobj.hover(
                  function(e){
                      var $targetul=$(this).children("ul:eq(0)")
                      this._offsets={left:$(this).offset().left, top:$(this).offset().top}
                      var menuleft=this.istopheader? 0 : this._dimensions.w
                      menuleft=(this._offsets.left+menuleft+this._dimensions.subulw>$(window).width())? (this.istopheader? -this._dimensions.subulw+this._dimensions.w : -this._dimensions.w)+1 : menuleft-1
                      
                      if ($targetul.queue().length<=1) //if 1 or less queued animations
                          $targetul.css({left:menuleft+"px", width:this._dimensions.subulw+'px'}).slideDown(jqueryslidemenu.animateduration.over)
                  },
                  function(e){
                      var $targetul=$(this).children("ul:eq(0)")
                      $targetul.slideUp(jqueryslidemenu.animateduration.out)
                  }
              ) //end hover
          }) //end $headers.each()
          $mainmenu.find("ul").css({display:'none', visibility:'visible'})
      }) //end document.ready
  }
  }
  
  //build menu with ID="mainnav" on page:
  jqueryslidemenu.buildmenu("mainmenu")