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(6,12). next(12,13). next(13,14). next(14,15). next(15,16). next(16,17). next(17,18). next(13,19). next(19,20). next(20,21). next(21,22). next(22,23). next(23,24). next(19,25). 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(5,34). next(34,35). next(35,36). next(36,37). next(37,38). next(38,39). next(39,40). next(40,41). next(41,42). next(42,43). next(43,44). next(44,45). next(40,46). next(46,47). next(47,48). next(48,49). next(49,50). doAt(startflow,4). doAt(a3,5). doAt(a24,6). doAt(a7,7). doAt(a13,8). doAt(a11,9). doAt(endflow,10). doAt(a12,12). doAt(a15,13). doAt(a10,14). doAt(a13,15). doAt(a11,16). doAt(endflow,17). doAt(a6,19). doAt(a9,20). doAt(a13,21). doAt(a11,22). doAt(endflow,23). doAt(a25,25). doAt(a16,26). doAt(a14,27). doAt(a1,28). doAt(a2,29). doAt(a13,30). doAt(a11,31). doAt(endflow,32). doAt(a4,34). doAt(a20,35). doAt(a18,36). doAt(a5,37). doAt(a17,38). doAt(a19,39). doAt(a22,40). doAt(a23,41). doAt(a13,42). doAt(a11,43). doAt(endflow,44). doAt(a8,46). doAt(a13,47). doAt(a11,48). doAt(endflow,49). leftrightnexts(20,25). leftrightnexts(14,19). leftrightnexts(7,12). leftrightnexts(41,46). leftrightnexts(6,34).