In this part, you will write regular expressions for 4 problems and create test cases for them (5 matching, 5 non-matching as previously). You will also practice interpreting a written specification into program requirements - remember, edge cases matter! An example of this is also shown further down.

1. Integer List: A list of comma-separated, positive integers surrounded by square brackets []. A optional single space character is allowed after the comma.
   • The number of integers is not specified, so an empty list ([]) is allowed.
   • The term comma-separated implies that a trailing comma ([1, 2, 3,]) is not allowed.
   • The single space character does not need to be consistent, so mixed spaces ([1,2, 3]) is allowed (this makes it a bit easier to implement).
   • Examples: [1], [1,2,3]
   • Non-Examples: 1,2,3, [1 2 3]