[1,2,1,0,3,2,4,1,5,2,6,1,5,4,0,7,2,6,5,8,3,8,5,9, 4,10,1,10,3,8,7,0,11,4,10,7,11,6,13,2,10,9,12,7, 14,1,15,2,13,8,15,4,16,1,13,10,14,9,16,5,17,2,13, 12,14,11,16,9,18,5,17,8,0,18,7,17,10,19,6,20,1,20, 3,15,14,17]