grep-like-tool

The problem statement is given here

Input Format

<number-of-test-cases>
<reg-ex-1>
<test-string-1>
.
.
.

Regular Expression Input follows the below grammar

R -> concat(R, R)
R -> union(R, R)
R -> star(R)
R -> symbol(C)
C -> <any-ascii-character>

For example, if (a + b)^*c is the regular expression, the input format will be

concat(star(symbol(a)),union(symbol(b),symbol(c)))

To test it, specify the input in a test file, say input.txt

and run it with

cargo run < input.txt

If the string is part of the regular expression, output will be "Yes" Else the output will be "No"

It has been tested with the sample input file given here