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(8,14). next(14,15). next(15,16). next(16,17). next(17,18). next(18,19). next(19,20). next(20,21). next(16,22). next(22,23). next(23,24). next(24,25). next(25,26). next(26,27). next(27,28). next(28,29). next(23,30). next(30,31). next(31,32). next(32,33). next(33,34). next(34,35). next(35,36). next(36,37). next(37,38). next(32,39). next(39,40). next(40,41). next(41,42). next(42,43). next(43,44). next(44,45). next(45,46). next(46,47). next(40,48). next(48,49). next(49,50). next(50,51). next(51,52). next(52,53). next(53,54). doAt(startflow,3). doAt(a14,5). doAt(a10,6). doAt(a19,7). doAt(a17,8). doAt(a1,9). doAt(a5,10). doAt(a8,11). doAt(endflow,12). doAt(a13,14). doAt(a24,15). doAt(a15,16). doAt(a21,17). doAt(a5,18). doAt(a8,19). doAt(endflow,20). doAt(a25,22). doAt(a7,23). doAt(a4,24). doAt(a20,25). doAt(a5,26). doAt(a8,27). doAt(endflow,28). doAt(a22,30). doAt(a2,31). doAt(a18,32). doAt(a16,33). doAt(a20,34). doAt(a5,35). doAt(a8,36). doAt(endflow,37). doAt(a3,39). doAt(a9,40). doAt(a23,41). doAt(a6,42). doAt(a20,43). doAt(a5,44). doAt(a8,45). doAt(endflow,46). doAt(a12,48). doAt(a6,49). doAt(a20,50). doAt(a5,51). doAt(a8,52). doAt(endflow,53). subsAt(a14,4). leftrightnexts(41,48). leftrightnexts(33,39). leftrightnexts(24,30). leftrightnexts(17,22). leftrightnexts(9,14).