[0,1,3,2,4,5,6,7,8,9,10,11,13,12,14,15,16,17,18, 19,30,31,33,32,34,35,36,37,38,39,20,21,23,22,24, 25,26,27,28,29,40,41,43,42,44,45,46,47,48,49,50, 51,53,52,54,55,56,57,58,59,60,61,63,62,64,65,66, 67,68]