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(12,16).
next(16,17).
next(17,18).
next(18,19).
next(19,20).
next(20,21).
next(17,22).
next(22,23).
next(23,24).
next(24,25).
next(25,26).
next(26,27).
next(27,28).
next(28,29).
next(25,30).
next(30,31).
next(31,32).
next(32,33).
next(33,34).
next(24,35).
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(44,45).
next(45,46).
next(42,47).
next(47,48).
next(48,49).
next(49,50).
doAt(startflow,6).
doAt(a4,9).
doAt(a6,11).
doAt(a2,12).
doAt(a10,13).
doAt(endflow,14).
doAt(a25,16).
doAt(a8,17).
doAt(a21,19).
doAt(endflow,20).
doAt(a18,22).
doAt(a13,23).
doAt(a23,24).
doAt(a7,25).
doAt(a3,27).
doAt(endflow,28).
doAt(a22,30).
doAt(a14,31).
doAt(endflow,33).
doAt(a11,35).
doAt(a9,36).
doAt(a1,37).
doAt(a20,38).
doAt(a12,39).
doAt(a15,40).
doAt(a5,41).
doAt(a19,42).
doAt(a16,43).
doAt(endflow,45).
doAt(a17,47).
doAt(endflow,49).
compAt(a6,x17,7).
compAt(a10,x7,8).
compAt(a10,x8,18).
compAt(a10,x8,26).
compAt(a10,x8,32).
compAt(a10,x8,44).
compAt(a10,x8,48).
subsAt(a6,10).
leftrightnexts(26,30).
leftrightnexts(43,47).
leftrightnexts(25,35).
leftrightnexts(18,22).
leftrightnexts(13,16).