(assume c language programming)

question 1

consider the following grammar:
s -> aa | bb
a -> b | aa
b -> a | abb
the following transfomation:

replace all substring of 'a' with the number of 'a's in that substring, always taking the maximum number of 'a's you can
replace any 'b' with 1
and the following operational semantics:

start each program with: val num = 0
for each symbok in the string from left to right:
if the symbol is an 'a' add: val num = num +1
if the symbol is an 'b' and is followed by the end of the string add: val num = 10*num+1
if the symbol is an 'b' and is folowed by an 'a': val num = 10*(10*num+1)
end each program with display num
if the "meaning" of a string in this language is the above transformation regarded as a decimal number, which statement about the operational semantics is true?

the operational semantics are almost completely wrong, and most rules need to be rewritten.

the operational semantics perfectly specify the dynamic semantics of this language.

the operational semantics require one of its rules to be modified before it is correct.

the operational semantics specify the dynamic semantics, but is considerably more complicated than needed.