local function dig()
    while turtle.detect() do
        turtle.dig()
        os.sleep(0.51)
    end
end

for cz = 1, 18 do
    dig()
    turtle.digDown()
    turtle.forward()

    if(cz % 2 == 0) then
        turtle.turnLeft()
        turtle.dig()
        turtle.select(1)
        turtle.place()
        turtle.turnRight()
    end
    dig()
    turtle.digUp()
    turtle.digDown()
    turtle.down()
    turtle.forward()
    dig()
    turtle.digDown()
    turtle.down()
    dig()
    turtle.forward()
    turtle.turnLeft()
end