tunnel_3x3_computer_craft

term.write("Please write the length of the tunnel")
local length = read()

while turtle.getFuelLevel() < length*7 do
 local q = turtle.getFuelLevel()
  if turtle.getFuelLevel() < length*7 then
   term.write("Fuel Level is at "..q.." But needs to be "..length*7)
   term.write("Please put Fuel in 1st slot")
   os.sleep(5)
   turtle.refuel()
  end
end

term.write("Mining a "..length.." block length tunnel")

   for a = 1,length do
      turtle.dig()
      turtle.forward()
      turtle.digUp()
      turtle.digDown()
      turtle.turnRight()
      turtle.dig()
      turtle.forward()
      turtle.digUp()
      turtle.digDown()
      turtle.back()
      turtle.turnLeft()
      turtle.turnLeft()
      turtle.dig()
      turtle.forward()
      turtle.digUp()
      turtle.digDown()
      turtle.back()
      turtle.turnRight()
     end

    for b = 1,length do
     turtle.back()
    end

   for c = 2,16 do
    turtle.select(c)
    turtle.dropDown(64)
   end

 turtle.select(1)