fillMax

turtle.forward()
x = 1
turtle.select(x)
while turtle.detectDown() == false do
  while turtle.detectDown() == false do
    if turtle.placeDown() == false then
      x = x+1
    end
    if x == 17 then
      turtle.back()
      turtle.back()
    else
      turtle.select(x)
    end
  end
  turtle.forward()
end