next(1,2). next(2,3). next(3,4). next(4,5). next(5,6). next(6,7). next(7,8). next(8,9). next(9,10). next(10,11). next(11,12). next(12,13). next(13,14). next(14,15). next(15,16). next(16,17). next(17,18). next(18,19). next(14,20). next(20,21). next(21,22). next(22,23). next(23,24). next(24,25). next(25,26). next(26,27). next(22,28). next(28,29). next(29,30). next(30,31). next(31,32). next(32,33). next(33,34). next(34,35). next(35,36). next(36,37). next(37,38). doAt(startflow,4). doAt(a24,6). doAt(a20,7). doAt(a15,8). doAt(a7,9). doAt(a25,10). doAt(a1,11). doAt(a4,12). doAt(a19,13). doAt(a12,14). doAt(a22,15). doAt(a23,16). doAt(a11,17). doAt(endflow,18). doAt(a3,20). doAt(a10,21). doAt(a17,22). doAt(a9,23). doAt(a5,24). doAt(a11,25). doAt(endflow,26). doAt(a6,28). doAt(a16,29). doAt(a8,30). doAt(a21,31). doAt(a13,32). doAt(a2,33). doAt(a18,34). doAt(a5,35). doAt(a11,36). doAt(endflow,37). compAt(a20,x17,5). leftrightnexts(23,28). leftrightnexts(15,20).