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(10,14).
next(14,15).
next(15,16).
next(9,17).
next(17,18).
next(7,19).
next(19,20).
next(20,21).
next(21,22).
next(22,23).
next(23,24).
next(24,25).
next(22,26).
next(26,27).
next(27,28).
next(21,29).
next(29,30).
next(6,31).
next(31,32).
next(32,33).
next(33,34).
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(41,45).
next(45,46).
next(46,47).
next(40,48).
next(48,49).
next(38,50).
next(50,51).
next(51,52).
next(52,53).
next(53,54).
next(54,55).
next(55,56).
next(56,57).
next(57,58).
next(55,59).
next(59,60).
next(60,61).
next(54,62).
next(62,63).
doAt(startflow,3).
doAt(a1,4).
doAt(a7,5).
doAt(a18,6).
doAt(a8,7).
doAt(a11,8).
doAt(a3,9).
doAt(a4,10).
doAt(a12,11).
doAt(endflow,12).
doAt(a19,14).
doAt(endflow,15).
doAt(endflow,17).
doAt(a20,19).
doAt(a13,20).
doAt(a3,21).
doAt(a4,22).
doAt(a12,23).
doAt(endflow,24).
doAt(a19,26).
doAt(endflow,27).
doAt(endflow,29).
doAt(a24,31).
doAt(a22,32).
doAt(a10,33).
doAt(a25,34).
doAt(a9,35).
doAt(a2,36).
doAt(a6,37).
doAt(a14,38).
doAt(a21,39).
doAt(a3,40).
doAt(a4,41).
doAt(a12,42).
doAt(endflow,43).
doAt(a19,45).
doAt(endflow,46).
doAt(endflow,48).
doAt(a17,50).
doAt(a5,51).
doAt(a15,52).
doAt(a16,53).
doAt(a3,54).
doAt(a4,55).
doAt(a12,56).
doAt(endflow,57).
doAt(a19,59).
doAt(endflow,60).
doAt(endflow,62).
leftrightnexts(11,14).
leftrightnexts(10,17).
leftrightnexts(23,26).
leftrightnexts(22,29).
leftrightnexts(8,19).
leftrightnexts(42,45).
leftrightnexts(41,48).
leftrightnexts(56,59).
leftrightnexts(55,62).
leftrightnexts(39,50).
leftrightnexts(7,31).