parity = true

while true do
	done = false
	i = 1
	while not done do
		if turtle.getItemCount(i) ~= 0 then
			turtle.select(i)
			done = true
		end
		i = i + 1
	end
	turtle.placeDown()
	if not turtle.forward() then
		if parity then
			turtle.turnRight()
			turtle.forward()
			turtle.turnRight()
		else
			turtle.turnLeft()
			turtle.forward()
			turtle.turnLeft()
		end
		parity = not parity
	end
end