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(15,19).
next(19,20).
next(20,21).
next(21,22).
next(19,23).
next(23,24).
next(24,25).
next(25,26).
next(23,27).
next(27,28).
next(28,29).
next(29,30).
next(30,31).
next(31,32).
next(14,33).
next(33,34).
next(7,35).
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(45,46).
next(46,47).
next(47,48).
next(45,49).
next(49,50).
next(50,51).
next(51,52).
next(49,53).
next(53,54).
next(54,55).
next(55,56).
next(53,57).
next(57,58).
next(58,59).
next(59,60).
next(60,61).
next(61,62).
next(44,63).
next(63,64).
doAt(startflow,3).
doAt(a6,5).
doAt(a11,6).
doAt(a9,7).
doAt(a20,8).
doAt(a19,9).
doAt(a21,10).
doAt(a16,11).
doAt(a12,12).
doAt(a23,13).
doAt(a25,14).
doAt(a4,15).
doAt(a18,16).
doAt(endflow,17).
doAt(a2,19).
doAt(a13,20).
doAt(endflow,21).
doAt(a22,23).
doAt(a14,24).
doAt(endflow,25).
doAt(a7,27).
doAt(a8,28).
doAt(a5,29).
doAt(a1,30).
doAt(endflow,31).
doAt(endflow,33).
doAt(a10,35).
doAt(a3,36).
doAt(a17,37).
doAt(a15,38).
doAt(a19,39).
doAt(a21,40).
doAt(a16,41).
doAt(a12,42).
doAt(a23,43).
doAt(a25,44).
doAt(a4,45).
doAt(a18,46).
doAt(endflow,47).
doAt(a2,49).
doAt(a13,50).
doAt(endflow,51).
doAt(a22,53).
doAt(a14,54).
doAt(endflow,55).
doAt(a7,57).
doAt(a8,58).
doAt(a5,59).
doAt(a1,60).
doAt(endflow,61).
doAt(endflow,63).
subsAt(a6,4).
leftrightnexts(24,27).
leftrightnexts(20,23).
leftrightnexts(16,19).
leftrightnexts(15,33).
leftrightnexts(54,57).
leftrightnexts(50,53).
leftrightnexts(46,49).
leftrightnexts(45,63).
leftrightnexts(8,35).