[0,1,0,1,2,3,2,1,0,1,2,3,4,5,6,7,8,9,8,7,6,5,4,3, 2,1,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17, 18,19,20,21,22,23,24,25,26,27,26,25,24,23,22,21, 20,19,18,17,16,15,14,13,12,11,10,9,8,7,6,5,4,3,2, 1,0,1,2,3,4,5,6,7]