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(8,13). next(13,14). next(14,15). next(15,16). next(16,17). next(14,18). next(18,19). next(19,20). next(20,21). next(21,22). next(19,23). 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(34,39). next(39,40). next(40,41). next(41,42). doAt(startflow,5). doAt(a3,7). doAt(a11,8). doAt(a9,10). doAt(endflow,11). doAt(a16,13). doAt(a17,14). doAt(a1,15). doAt(endflow,16). doAt(a23,18). doAt(a7,19). doAt(a22,20). doAt(endflow,21). doAt(a24,23). doAt(a20,24). doAt(a2,25). doAt(a19,26). doAt(a5,27). doAt(a8,28). doAt(a6,29). doAt(a4,30). doAt(a25,31). doAt(a15,32). doAt(a18,33). doAt(a13,34). doAt(a21,35). doAt(a12,36). doAt(endflow,37). doAt(a14,39). doAt(a12,40). doAt(endflow,41). compAt(a3,x8,6). compAt(a9,x3,9). leftrightnexts(35,39). leftrightnexts(20,23). leftrightnexts(15,18). leftrightnexts(9,13).