package body VEREM_E is	-- verem kivetelkezelessel

        procedure Push ( v: in out Verem; e: Elem ) is
	begin	v.top := new Node'(e,v.top);	end Push;

        procedure Pop ( v: in out Verem ) is
	begin	
		if isEmpty(v) then raise MAR_URES;
		else v.top := v.top.next;
		end if;	
	end Pop;

        function Top ( v: Verem ) return Elem is
	begin	return v.top.data;	
	exception 
		when CONSTRAINT_ERROR => raise MAR_URES;
	end Top;

	function isEmpty ( v: Verem ) return BOOLEAN is
	begin	return (v.top = null);	end isEmpty;

end VEREM_E;