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(9,13).
next(13,14).
next(14,15).
next(15,16).
next(16,17).
next(17,18).
next(6,19).
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(28,29).
next(29,30).
next(30,31).
next(5,32).
next(32,33).
next(33,34).
next(34,35).
next(35,36).
next(36,37).
next(37,38).
next(35,39).
next(39,40).
next(40,41).
next(41,42).
next(42,43).
next(43,44).
next(4,45).
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(50,54).
next(54,55).
next(55,56).
next(56,57).
next(57,58).
next(58,59).
doAt(startflow,3).
doAt(a2,4).
doAt(a7,5).
doAt(a5,6).
doAt(a19,7).
doAt(a12,8).
doAt(a1,9).
doAt(a17,10).
doAt(endflow,11).
doAt(a20,13).
doAt(a4,14).
doAt(a3,15).
doAt(a11,16).
doAt(endflow,17).
doAt(a14,19).
doAt(a16,20).
doAt(a12,21).
doAt(a1,22).
doAt(a17,23).
doAt(endflow,24).
doAt(a20,26).
doAt(a4,27).
doAt(a3,28).
doAt(a11,29).
doAt(endflow,30).
doAt(a8,32).
doAt(a18,33).
doAt(a12,34).
doAt(a1,35).
doAt(a17,36).
doAt(endflow,37).
doAt(a20,39).
doAt(a4,40).
doAt(a3,41).
doAt(a11,42).
doAt(endflow,43).
doAt(a9,45).
doAt(a15,46).
doAt(a10,47).
doAt(a13,48).
doAt(a12,49).
doAt(a1,50).
doAt(a17,51).
doAt(endflow,52).
doAt(a20,54).
doAt(a4,55).
doAt(a3,56).
doAt(a11,57).
doAt(endflow,58).
leftrightnexts(10,13).
leftrightnexts(23,26).
leftrightnexts(7,19).
leftrightnexts(36,39).
leftrightnexts(6,32).
leftrightnexts(51,54).
leftrightnexts(5,45).