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(7,11). next(11,12). next(12,13). next(13,14). next(11,15). next(15,16). next(16,17). next(17,18). next(4,19). next(19,20). 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(30,31). next(31,32). next(32,33). next(33,34). next(34,35). next(35,36). next(36,37). next(37,38). next(35,39). next(39,40). next(40,41). next(41,42). next(39,43). next(43,44). next(44,45). next(45,46). doAt(startflow,3). doAt(a23,4). doAt(a3,5). doAt(a5,6). doAt(a7,7). doAt(a9,8). doAt(endflow,9). doAt(a24,11). doAt(a22,12). doAt(endflow,13). doAt(a20,15). doAt(a17,16). doAt(endflow,17). doAt(a19,19). doAt(a11,20). doAt(a12,21). doAt(a1,22). doAt(a25,23). doAt(a13,24). doAt(a6,25). doAt(a4,26). doAt(a15,27). doAt(a21,28). doAt(a16,29). doAt(a8,30). doAt(a10,31). doAt(a2,32). doAt(a18,33). doAt(a5,34). doAt(a7,35). doAt(a9,36). doAt(endflow,37). doAt(a24,39). doAt(a22,40). doAt(endflow,41). doAt(a20,43). doAt(a17,44). doAt(endflow,45). leftrightnexts(12,15). leftrightnexts(8,11). leftrightnexts(40,43). leftrightnexts(36,39). leftrightnexts(5,19).