9,8,6,7,20,19,21,24,22,23,32,33,31,2,3,0,1,40,38,39,48,49,27,28,29,16,18,17,5,4,42,41,43,30,37,35,34,36,26,25,13,14,15,46,45,47,44,10,12,11