mine.lua

function digit()
    while turtle.detect() do
        turtle.dig()
        os.sleep(0.5)
    end
    turtle.forward()
    while turtle.detectDown() or turtle.detectUp() do
        turtle.digUp()
        turtle.digDown()
    end
end

local run = 0

term.write("Length: ")

run = read()

for i = 1, run do
    digit()
    turtle.turnLeft()
    digit()
    turtle.turnRight()
    turtle.turnRight()
    turtle.forward()
    digit()
    turtle.turnLeft()
    turtle.turnLeft()
    turtle.forward()
    turtle.turnRight()
end

turtle.down()
turtle.turnLeft()
turtle.turnLeft()

for x = 1, run do
    turtle.forward()
end