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(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(30,34). next(34,35). next(35,36). next(29,37). next(37,38). next(38,39). next(39,40). next(40,41). next(18,42). next(42,43). doAt(startflow,7). doAt(a20,9). doAt(a10,11). doAt(a19,12). doAt(a9,13). doAt(a11,14). doAt(a22,15). doAt(a6,16). doAt(a16,17). doAt(a15,18). doAt(a1,19). doAt(a12,20). doAt(endflow,21). doAt(a4,23). doAt(a13,24). doAt(a18,25). doAt(a8,26). doAt(a7,27). doAt(a2,28). doAt(a14,29). doAt(a25,30). doAt(a21,31). doAt(endflow,32). doAt(a17,34). doAt(endflow,35). doAt(a24,37). doAt(a23,38). doAt(a5,39). doAt(endflow,40). doAt(endflow,42). compAt(a20,x9,8). subsAt(a10,10). leftrightnexts(31,34). leftrightnexts(30,37). leftrightnexts(20,23). leftrightnexts(19,42).