Turtle Block Placer/Breaker

turtle.up()
turtle.up()
turtle.turnLeft()
turtle.turnLeft()
    for s=1,16 do
      turtle.select(s)
      turtle.suck()
    end
turtle.down()

items=0
for n=1,16 do
  turtle.select(n)
  items = items + turtle.getItemCount()
end
    total=items*2
    level=turtle.getFuelLevel()
    if total>level then
        turtle.down()
        turtle.turnRight()
        turtle.turnRight()
    print("Ups, mein Treibstoff reicht nicht daf\195\188r aus!")
    print("Bitte vorher auftanken und neu starten!")
    else

 for i=1,16 do
  turtle.select(i)
    while turtle.getItemCount(i) >0 do
    turtle.back()
    sleep(.5)
    turtle.place()
  end
end

while turtle.detect() do
      turtle.dig()
      sleep(.5)
      turtle.forward()
end

turtle.down()
sleep(.5)
    for d=1,16 do
    turtle.select(d)
       turtle.drop()
    end

turtle.turnRight()
turtle.turnRight()

end