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(22,23). next(23,24). next(21,25). next(25,26). next(26,27). next(27,28). next(25,29). next(29,30). next(30,31). next(31,32). next(32,33). next(33,34). next(34,35). next(32,36). next(36,37). next(37,38). next(20,39). next(39,40). next(40,41). doAt(startflow,6). doAt(a5,7). doAt(a4,9). doAt(a7,10). doAt(a22,11). doAt(a2,12). doAt(a24,13). doAt(a20,14). doAt(a12,15). doAt(a9,16). doAt(a11,17). doAt(a18,18). doAt(a10,19). doAt(a8,20). doAt(a21,21). doAt(a13,22). doAt(endflow,23). doAt(a15,25). doAt(a1,26). doAt(endflow,27). doAt(a23,29). doAt(a14,30). doAt(a16,31). doAt(a17,32). doAt(a6,33). doAt(endflow,34). doAt(a3,36). doAt(endflow,37). doAt(a19,39). doAt(endflow,40). compAt(a22,x20,8). leftrightnexts(33,36). leftrightnexts(26,29). leftrightnexts(22,25). leftrightnexts(21,39).