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(18,19).
next(16,20).
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(28,29).
next(29,30).
next(30,31).
next(31,32).
next(32,33).
next(33,34).
next(34,35).
next(35,36).
next(33,37).
next(37,38).
next(38,39).
next(39,40).
next(29,41).
next(41,42).
next(42,43).
next(43,44).
next(44,45).
next(45,46).
next(46,47).
next(47,48).
next(48,49).
next(49,50).
next(50,51).
next(51,52).
next(52,53).
next(53,54).
next(51,55).
next(55,56).
next(56,57).
next(57,58).
doAt(startflow,5).
doAt(a5,6).
doAt(a20,8).
doAt(a3,10).
doAt(a13,11).
doAt(a25,12).
doAt(endflow,13).
doAt(a4,15).
doAt(a18,16).
doAt(a14,17).
doAt(endflow,18).
doAt(a34,20).
doAt(a29,21).
doAt(a16,22).
doAt(a8,23).
doAt(a11,24).
doAt(a26,25).
doAt(a9,26).
doAt(a30,27).
doAt(a33,28).
doAt(a31,29).
doAt(a17,30).
doAt(a21,31).
doAt(a1,32).
doAt(a23,33).
doAt(a28,34).
doAt(endflow,35).
doAt(a6,37).
doAt(a15,38).
doAt(endflow,39).
doAt(a27,41).
doAt(a10,42).
doAt(a24,43).
doAt(a32,44).
doAt(a22,45).
doAt(a12,46).
doAt(a2,47).
doAt(a19,48).
doAt(a35,49).
doAt(a1,50).
doAt(a23,51).
doAt(a28,52).
doAt(endflow,53).
doAt(a6,55).
doAt(a15,56).
doAt(endflow,57).
subsAt(a20,7).
subsAt(a3,9).
leftrightnexts(34,37).
leftrightnexts(52,55).
leftrightnexts(30,41).
leftrightnexts(17,20).
leftrightnexts(12,15).