Minecraft clearArea Clean

lenght = 3
rows = 3
height = 3
yAlt = 1

function clearLine()
    for i=1, lenght - 1 do
        turtle.dig()
        turtle.forward()
    end
end

function clearLayer()
    for i=1, rows do
        clearLine()
        if rows%2 == 0 and yAlt%2 == 0 then
            if i%2 == 1 and i < rows then
                turtle.turnLeft()
                turtle.dig()
                turtle.forward()
                turtle.turnLeft()
            elseif i < rows then
                turtle.turnRight()
                turtle.dig()
                turtle.forward()
                turtle.turnRight()
            end
        else
            if i%2 == 1 and i < rows then
                turtle.turnRight()
                turtle.dig()
                turtle.forward()
                turtle.turnRight()
            elseif i < rows then
                turtle.turnLeft()
                turtle.dig()
                turtle.forward()
                turtle.turnLeft()
            end
        end
    end
end

function clearPlatformArea()
    while height > 0 do
        clearLayer()
        height = height - 1
        yAlt = yAlt + 1
        if height > 0 then
            turtle.digUp()
            turtle.up()
            turtle.turnRight()
            turtle.turnRight()
        end
    end
end

turtle.dig()
turtle.forward()
clearPlatformArea()