function mydig()
	if turtle.detect() then
		turtle.dig()
	end
end

function mydigdown()
	if turtle.detectDown() then
		turtle.digDown()
	end
end

function fuelcheck()
    if turtle.getFuelLevel() < 1 then
	    turtle.refuel()
	end
end

for z=0,4 do
  dirx=0
  for x=0,4 do

    fuelcheck()

    for y=0,4 do
	  mydig()
	  turtle.forward()
	end
	if (x < 4) then
	  if (dirx == 0) then
	    turtle.turnRight()
	    mydig()
	    turtle.forward()
	    turtle.turnRight()
	    dirx=1
	  else
	    turtle.turnLeft()
	    mydig()
	    turtle.forward()
	    turtle.turnLeft()
	    dirx=0
	  end
	end
  end
  turtle.turnRight()
  turtle.turnRight()

  mydigdown()
  turtle.down()
end