I have to write regular expressions, but it seems that I keep doing something wrong.
Here, I have to write an expression containing any of the words: linux windows solaris macos. Below, is my code.
"[linux windows solaris macos]"
Here, I have to write an expression that matches either a ddddddddd, or broken up with hyphens in the standard way: ddd-dd-dddd for a Social Security number. Below, is my code.
What am I doing wrong?