Exploiting Regular Expressions
A regular expression (or regex) is basically a search pattern. For example, the expression
[cb]atwill match both cat and bat. This isn’t a regex tutorial so if you don’t know much about regex, go through this amazing cheat sheet before reading any further.
Let’s get started with some basics anyway :)
+ is a repetition operator and matches repetition of characters, patterns or groups.
ca+t will match caaaat