mine.lua

x = read()
x = tonumber(x)
y = x
z = x
function dig()
    while x ~= 0 do
        turtle.dig()
        turtle.digUp()
        turtle.digDown()
        turtle.forward()
        x = x - 1
    end
    turtle.digUp()
    turtle.digDown()
    x = y
end
function turnLeft()
    turtle.turnLeft()
    turtle.dig()
    turtle.forward()
    turtle.digUp()
    turtle.digDown()
    turtle.turnLeft()
end
function turnRight()
    turtle.turnRight()
    turtle.dig()
    turtle.forward()
    turtle.digUp()
    turtle.digDown()
    turtle.turnRight()
end
function down()
    if z % 2 == 0 then
        turtle.turnLeft()
    else
        turtle.turnRight()
    end
    turtle.down()
    turtle.digDown()
    turtle.down()
    turtle.digDown()
    turtle.down()
end
function corridor()
    if y % 2 == 0 then
        while z ~= 0 do
            dig()
            turnLeft()
            dig()
            z = z - 2
            if z ~= 0 then
                turnRight()
            end
        end
        z = y
        else
            dig()
            turnLeft()
            z = z - 1
            while z ~= 0 do
                dig()
                turnRight()
                dig()
                z = z - 2
                if z ~= 0 then
                    turnLeft()
                end
            end
        end
    end
while true do
    corridor()
    down()
end