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(18,19).
next(19,20).
next(15,21).
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(14,30).
next(30,31).
next(31,32).
next(32,33).
next(33,34).
next(34,35).
next(35,36).
next(31,37).
next(37,38).
next(38,39).
next(39,40).
next(40,41).
next(41,42).
next(42,43).
next(30,44).
next(44,45).
next(45,46).
next(46,47).
next(47,48).
next(13,49).
next(49,50).
next(50,51).
next(51,52).
next(52,53).
next(53,54).
doAt(startflow,6).
doAt(a19,7).
doAt(a24,8).
doAt(a16,10).
doAt(a7,12).
doAt(a13,13).
doAt(a21,14).
doAt(a17,15).
doAt(a5,16).
doAt(a2,17).
doAt(a1,18).
doAt(endflow,19).
doAt(a11,21).
doAt(a14,22).
doAt(a18,23).
doAt(a15,24).
doAt(a9,25).
doAt(a2,26).
doAt(a1,27).
doAt(endflow,28).
doAt(a22,30).
doAt(a25,31).
doAt(a3,32).
doAt(a2,33).
doAt(a1,34).
doAt(endflow,35).
doAt(a12,37).
doAt(a6,38).
doAt(a23,39).
doAt(a2,40).
doAt(a1,41).
doAt(endflow,42).
doAt(a8,44).
doAt(a2,45).
doAt(a1,46).
doAt(endflow,47).
doAt(a20,49).
doAt(a10,50).
doAt(a2,51).
doAt(a1,52).
doAt(endflow,53).
subsAt(a16,9).
subsAt(a7,11).
leftrightnexts(16,21).
leftrightnexts(32,37).
leftrightnexts(31,44).
leftrightnexts(15,30).
leftrightnexts(14,49).