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(5,11). next(11,12). next(12,13). next(13,14). next(14,15). next(15,16). next(16,17). next(13,18). next(18,19). 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(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(31,37). next(37,38). next(38,39). next(39,40). next(40,41). next(41,42). next(42,43). doAt(startflow,3). doAt(a13,4). doAt(a23,5). doAt(a12,6). doAt(a2,7). doAt(a16,8). doAt(endflow,9). doAt(a17,11). doAt(a19,12). doAt(a24,13). doAt(a8,14). doAt(a16,15). doAt(endflow,16). doAt(a3,18). doAt(a25,19). doAt(a9,20). doAt(a7,21). doAt(a20,22). doAt(a4,23). doAt(a15,24). doAt(a16,25). doAt(endflow,26). doAt(a22,28). doAt(a14,29). doAt(a10,30). doAt(a11,31). doAt(a1,32). doAt(a15,33). doAt(a16,34). doAt(endflow,35). doAt(a5,37). doAt(a18,38). doAt(a21,39). doAt(a15,40). doAt(a16,41). doAt(endflow,42). leftrightnexts(32,37). leftrightnexts(23,28). leftrightnexts(14,18). leftrightnexts(6,11).