Recursive Descent Parsing
Program must be written in java and it w ill not have to handle whites pace when parsing the strin g, i.e. " " and similar are illegal characters in this language.
Consider the following BNF grammar:
A -> I = E | E
E -> T + E | T - E | T
T -> F * T | F / T | F
F -> P ^ F | P
P -> I | L | UI | UL | (A)
U -> + | - | !
I -> C | CI
C -> a | b | ... | y | z
L -> D | DL
D -> 0 | 1 | ... | 8 | 9
Using the tech nique described in class implement a recursive descent parser that recognizes strings in this language. Input shoul d be from a file called input.txt and output should be to the console. An example session might look like this:
String read from file: a=a+b-c*d
The string "a=a+b-c*d" is in the languag e .
String read from file: a=a**b++c
The string "a=a**b++c" is not in the langu age.