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(9,20). next(20,21). next(21,22). next(22,23). next(23,24). next(24,25). next(25,26). next(26,27). next(27,28). next(28,29). next(29,30). next(21,31). next(31,32). next(32,33). next(33,34). next(34,35). next(35,36). next(36,37). next(37,38). next(38,39). next(39,40). next(40,41). next(41,42). next(42,43). next(43,44). next(44,45). next(34,46). next(46,47). next(47,48). next(48,49). next(49,50). next(50,51). next(51,52). next(52,53). next(53,54). next(54,55). next(55,56). next(56,57). next(57,58). doAt(startflow,4). doAt(a4,6). doAt(a2,8). doAt(a11,9). doAt(a3,10). doAt(a25,11). doAt(a5,12). doAt(a24,13). doAt(a10,14). doAt(a17,15). doAt(a13,16). doAt(a9,17). doAt(endflow,18). doAt(a15,20). doAt(a6,21). doAt(a14,22). doAt(a5,23). doAt(a24,24). doAt(a10,25). doAt(a17,26). doAt(a13,27). doAt(a9,28). doAt(endflow,29). doAt(a12,31). doAt(a21,32). doAt(a7,33). doAt(a16,34). doAt(a8,35). doAt(a23,36). doAt(a20,37). doAt(a5,38). doAt(a24,39). doAt(a10,40). doAt(a17,41). doAt(a13,42). doAt(a9,43). doAt(endflow,44). doAt(a18,46). doAt(a1,47). doAt(a19,48). doAt(a23,49). doAt(a20,50). doAt(a5,51). doAt(a24,52). doAt(a10,53). doAt(a17,54). doAt(a13,55). doAt(a9,56). doAt(endflow,57). compAt(a4,x17,5). subsAt(a2,7). leftrightnexts(35,46). leftrightnexts(22,31). leftrightnexts(10,20).