Longest Regex Match Substring

Problem Statement

Longest Regex Match Substring Problem Description Amazon is developing a string matching library. You are to develop a service that finds the longest substring that matches a given regex. More formally, you are given two strings, a text string sourceString , and a regex expression pattern . The string pattern contains exactly one wildcard character ('*'). A wildcard character ('*') matches any sequence of zero or more lowercase English characters. A regex matches some string if it is possible to replace the wildcard character with some sequence of characters such that the regex expression becomes equal to the string. No other character can be changed. For example, regex 'a*b' matches 'ab', 'aab', 'aaab', 'b', and 'aaaab'. It does not match 'acb', 'a*c', 'b*a'. Return the length of the longest substring of sourceString that matches the expression pattern . Return -1 if there is no such substring. Note: A substring is a contiguous sequence of characters within a string. Function Descript