CC: Borehole

-- borehole
turtle.refuel()
local y = 0
turtle.digDown()
while turtle.down() do
  y = y-1
    turtle.digDown()
  if turtle.getFuelLevel() < math.abs(y)+10 then
    print('Not enought fuel!')
    break
  end
end
while y < 0 do
  turtle.up()
  y = y+1
end
print('Done')