minecraft hopper

--pastebin code: mAT9f0dy

while true do
   a = 0
   b = 0
   for i = 1, 16 do
      turtle.suckUp()
      a = a+1
      sleep(0.5)
      if turtle.getItemCount(a) > b then
         turtle.select(a)
         while turtle.dropDown() == false do
            term.setCursorPos(1, 1)
            print("Master, the buffer below me is full!")
            sleep(3)
            shell.run("clear")
         end
      end
   end
   shell.run("clear")
   term.setCursorPos(1, 1)
   print("I am currently working as a hopper")
   a = 0
end