6

 3   X11 6  X12 8  X13 9
 2   X22  X31
10   R 1000  E 1001  E 1000  E 1001  E 1000  E 1000  A 1006  R 1007  A 1008  R 1009

 3   X21 0  X22 2  X23 5
 3   X11  X13  X31
 8   E 2001  E 2000  R 2002  E 2000  E 2001  R 2005  E 2001  E 2002

 1   X31 2
 0
 3   A 3000  I 3701  A 3002

 0
 3   X31  X11  X22
 6   R 4000  E 4000  E 4001  R 4003  R 4004  E 4002

 00
 00
 3    R 5000  I 5987  R 5002

 1   X61 2
 1   X31
 6   R 6000  E 6000  A 6002  A 6003  R 6004  I 6005