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(8,12). next(12,13). next(13,14). next(14,15). next(6,16). 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(25,26). next(26,27). next(27,28). next(25,29). next(29,30). next(30,31). next(31,32). next(32,33). next(24,34). next(34,35). next(35,36). next(36,37). next(34,38). next(38,39). next(39,40). doAt(startflow,3). doAt(a9,5). doAt(a22,6). doAt(a20,7). doAt(a12,8). doAt(a23,9). doAt(endflow,10). doAt(a10,12). doAt(a25,13). doAt(endflow,14). doAt(a1,16). doAt(a2,17). doAt(a18,18). doAt(a16,19). doAt(a15,20). doAt(a6,21). doAt(a21,22). doAt(a3,23). doAt(a13,24). doAt(a7,25). doAt(a5,26). doAt(endflow,27). doAt(a11,29). doAt(a17,30). doAt(a4,31). doAt(endflow,32). doAt(a14,34). doAt(a19,35). doAt(endflow,36). doAt(a24,38). doAt(endflow,39). compAt(a9,x3,4). leftrightnexts(9,12). leftrightnexts(26,29). leftrightnexts(35,38). leftrightnexts(25,34). leftrightnexts(7,16).