sample1

turtle.digDown()
turtle.down()

function row()
  for i = 1,4 do
    turtle.dig()
    turtle.forward()
  end
end

function rightTurn()
  turtle.turnRight()
  turtle.dig()
  turtle.forward()
  turtle.turnRight()
end

function leftTurn()
  turtle.turnLeft()
  turtle.dig()
  turtle.forward()
  turtle.turnLeft()
end

row()
turnRight()
row()
turnLeft()
row()
turnRight()
row()
turnLeft()
row()