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(12,16). next(16,17). next(17,18). next(18,19). next(19,20). next(20,21). next(21,22). next(22,23). next(23,24). next(24,25). next(22,26). next(26,27). next(27,28). next(21,29). next(29,30). next(18,31). 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(38,42). next(42,43). next(43,44). next(37,45). next(45,46). doAt(startflow,3). doAt(a19,4). doAt(a9,5). doAt(a25,6). doAt(a12,7). doAt(a16,8). doAt(a15,9). doAt(a13,10). doAt(a8,11). doAt(a20,12). doAt(a14,13). doAt(endflow,14). doAt(a7,16). doAt(a5,17). doAt(a10,18). doAt(a3,19). doAt(a4,20). doAt(a23,21). doAt(a18,22). doAt(a21,23). doAt(endflow,24). doAt(a6,26). doAt(endflow,27). doAt(endflow,29). doAt(a17,31). doAt(a24,32). doAt(a11,33). doAt(a22,34). doAt(a1,35). doAt(a4,36). doAt(a23,37). doAt(a18,38). doAt(a21,39). doAt(endflow,40). doAt(a6,42). doAt(endflow,43). doAt(endflow,45). leftrightnexts(23,26). leftrightnexts(22,29). leftrightnexts(39,42). leftrightnexts(38,45). leftrightnexts(19,31). leftrightnexts(13,16).