If you're unfamiliar with finger trees, I recommend staring at this [1] for a while. [1] http://commons.wikimedia.org/wiki/File:2-3_finger_tree,_sample_tree.sv

If you're unfamiliar with finger trees, I recommend staring at this [1] for a while. [1] http://commons.wikimedia.org/wiki/File:2-3_finger_tree,_sample_tree.svg http://commons.wikimedia.org/wiki/File:2-3_finger_tree,_samp...