1, 2, 3, 4, 5 and 6 paths can be done by choosing YES at the beginning; 7, 8, 9, 10, 11, 12 and 13 paths can be done by choosing NO. 11, 12 and 13 are almost the same, 3 and 7, 4 and 8, 5 and 9, 6 and 10 are similar too.
