1 ( 1 ) 1 + 1 * 1 e 1 O 1 a

S -> # A # | # B # | # C # | # D # | e | O

A -> e+ A_B # | # C + A_C # | # B + A_B # | # D + A_D #
A_t -> # B + A_B # | # D + A_D #
A_C -> # C # | # C + A_C # | # A_B #
A_B -> # B # | # B + A_D # | # A_D #
A_D -> # D # | # D + A_D #

B -> # C # B_A # | ( A ) B_A # | # D # B_D #
B_A -> ( A ) | ( A ) B_A # | # B_D #
B_D -> # D # | # D # B_D #

C -> ( A_t )* | ( B )* | # D *

D -> a