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(11,15).
next(15,16).
next(16,17).
next(17,18).
next(15,19).
next(19,20).
next(20,21).
next(7,22).
next(22,23).
next(23,24).
next(24,25).
next(25,26).
next(26,27).
next(27,28).
next(28,29).
next(26,30).
next(30,31).
next(31,32).
next(32,33).
next(30,34).
next(34,35).
next(35,36).
next(22,37).
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(45,46).
next(43,47).
next(47,48).
next(48,49).
next(49,50).
next(47,51).
next(51,52).
next(52,53).
next(39,54).
next(54,55).
next(55,56).
next(56,57).
next(57,58).
next(58,59).
next(59,60).
next(60,61).
next(61,62).
next(62,63).
next(63,64).
next(64,65).
next(65,66).
next(63,67).
next(67,68).
next(68,69).
next(69,70).
next(67,71).
next(71,72).
next(72,73).
doAt(startflow,3).
doAt(a12,5).
doAt(a2,6).
doAt(a6,7).
doAt(a7,8).
doAt(a4,9).
doAt(a8,10).
doAt(a5,11).
doAt(a16,12).
doAt(endflow,13).
doAt(a24,15).
doAt(a21,16).
doAt(endflow,17).
doAt(a17,19).
doAt(endflow,20).
doAt(a25,22).
doAt(a10,23).
doAt(a4,24).
doAt(a8,25).
doAt(a5,26).
doAt(a16,27).
doAt(endflow,28).
doAt(a24,30).
doAt(a21,31).
doAt(endflow,32).
doAt(a17,34).
doAt(endflow,35).
doAt(a13,37).
doAt(a23,38).
doAt(a19,39).
doAt(a3,40).
doAt(a4,41).
doAt(a8,42).
doAt(a5,43).
doAt(a16,44).
doAt(endflow,45).
doAt(a24,47).
doAt(a21,48).
doAt(endflow,49).
doAt(a17,51).
doAt(endflow,52).
doAt(a1,54).
doAt(a14,55).
doAt(a22,56).
doAt(a18,57).
doAt(a11,58).
doAt(a20,59).
doAt(a15,60).
doAt(a4,61).
doAt(a8,62).
doAt(a5,63).
doAt(a16,64).
doAt(endflow,65).
doAt(a24,67).
doAt(a21,68).
doAt(endflow,69).
doAt(a17,71).
doAt(endflow,72).
subsAt(a12,4).
leftrightnexts(16,19).
leftrightnexts(12,15).
leftrightnexts(31,34).
leftrightnexts(27,30).
leftrightnexts(48,51).
leftrightnexts(44,47).
leftrightnexts(68,71).
leftrightnexts(64,67).
leftrightnexts(40,54).
leftrightnexts(23,37).
leftrightnexts(8,22).