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(17,21).
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(26,30).
next(30,31).
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(32,40).
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(21,49).
next(49,50).
next(50,51).
doAt(startflow,7).
doAt(a16,9).
doAt(a7,11).
doAt(a12,12).
doAt(a19,14).
doAt(a4,16).
doAt(a6,17).
doAt(a2,18).
doAt(endflow,19).
doAt(a21,21).
doAt(a18,22).
doAt(a22,23).
doAt(endflow,24).
doAt(a14,26).
doAt(a1,27).
doAt(endflow,28).
doAt(a15,30).
doAt(a5,31).
doAt(a10,32).
doAt(a23,33).
doAt(a9,34).
doAt(a13,35).
doAt(a25,36).
doAt(a20,37).
doAt(endflow,38).
doAt(a17,40).
doAt(a11,41).
doAt(a3,42).
doAt(a9,43).
doAt(a13,44).
doAt(a25,45).
doAt(a20,46).
doAt(endflow,47).
doAt(a24,49).
doAt(endflow,50).
compAt(a4,x9,10).
compAt(a4,x23,13).
compAt(a4,x11,15).
subsAt(a16,8).
leftrightnexts(33,40).
leftrightnexts(27,30).
leftrightnexts(23,26).
leftrightnexts(22,49).
leftrightnexts(18,21).