x1  igw
a      m5f
d         77
x3          a
x3           b
e             44
d               5

a :     m[0-9]*[a-z]
x1:     [a-z]([a-z][a-z])*
b :     [0-9]*f[0-9]*
x2:     ([0-9][a-z])*
d :     [13579]*
        (1|3|5|7|9)*
e :     00|11|22|...|99
x3:     .


S -> BCA | CdC
A -> e | BA
B -> b
C -> a | ϵ

FIRST
------
S   BC  d   | abd
A   B   e   | be
B       b   | b
C       a   | a

FOLLOW
-------
S   #                       | #         | #
A   FOLLOW(S)               |       S   | #
B   FIRST(C),FIRST(A)       | abe       | abe
C   FIRST(A),d,FOLLOW(S)    | bed   S   | bde#

    a           b           d           e           #
S   (CdC,2)     (BCA,1)     (CdC,2)
A               (BA,4)                  (e,3)
B               (b,5)
C   (a,6)       (ϵ,7)       (ϵ,7)       (ϵ,7)       (ϵ,7)