--turtle square builder

function stopForBricks()
	print("out of bricks, fill'er up and press c")
	while true do
		local event, character = os.pullEvent()
		if event == "char" and character == "c" then break end
	end
end

--main program

local slotNum = 1
local side = 1

while true do
	for i = 1,17 do
		if turtle.getItemCount(slotNum) == 0 then
			slotNum = slotNum + 1
			if slotNum == 17 then
				stopForBricks()
				slotNum = 1
			end
		end
		turtle.select(slotNum)
		turtle.placeDown()
		turtle.forward()
	end

	turtle.turnRight()
	side = side + 1

	if side == 5 then
		turtle.up()
		side = 1
	end
end