mine2

if #arg == 0 then
    arg = { ... }
end

local xSize, ySize, zSize = tonumber(arg[1]), tonumber(arg[2]), tonumber(arg[3])

local function forward()
    repeat
        turtle.dig()
    until turtle.forward()
end

local function mineX()
    for _ = 1, xSize do
        turtle.digUp()
        turtle.digDown()

        forward()
    end

    turtle.digUp()
    turtle.digDown()
end

local function mineZ(y)
    for z = 1, zSize do
        mineX()

        if z == zSize then
            break
        end

        local d = 0

        -- only alternate if even z size
        if zSize % 2 == 0 then
            d = y - 1
        end

        if z % 2 ~= d then
            turtle.turnRight()

            forward()

            turtle.turnRight()
        else
            turtle.turnLeft()

            forward()

            turtle.turnLeft()
        end
    end
end

for y = 1, math.abs(ySize) do
    mineZ(y)

    turtle.turnRight()
    turtle.turnRight()

    if y == math.abs(ySize) then
        break
    end

    if ySize < 0 then
        for _ = 1, 3 do
            turtle.digDown()
            turtle.down()
        end
    else
        for _ = 1, 3 do
            turtle.digUp()
            turtle.up()
        end
    end
end