fun recurse_balance(nodes: Array[String], len: Int): String do
		var finpos = 0
		var stpos = 0
		while stpos < len do
			if len - stpos > 1 then
				nodes[finpos] = new Concat(nodes[stpos], nodes[stpos + 1])
				stpos += 2
			else
				nodes[finpos] = nodes[stpos]
				stpos += 1
			end
			finpos += 1
		end
		if finpos == 1 then return nodes[0]
		return recurse_balance(nodes, finpos)
	end