elevator.lua

-- size 3
-- going up 1 3 5
-- going down 5 3 4 4 1 2 2 3 3

-- size 5
-- going up 1 3 5 7 9
-- going down 9 7 8 8 5 6 6 7 7 3 4 4 5 5 1 2 2 3 3 4 4

-- string.format is quite a bit of typing
_ = string.format;

(function(height)

	local count = 0
	-- increment + print the current step
	local function step()
		count = count + 1
		return count
	end

	print (_("Elevator shaft height: %d blocks", height))
	print "Calculating steps..."
	
	print "Going up!"

	for i=0,height-1 do
		print (_("Step %d = %d", step(), i*2+1))
	end
	
	print "Going down!"
	
	local max = math.pow(height,2)
	for i=1,max do
		-- lua doesn't like me iterating in reverse, apparently
		local action = max - i+1
		print (_("Step %d = %d", step(), action/2+1))
	end
end)(3)