JavaScript Regex adding a rule for forward slash only
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Ok I am need of a rule that can report true on only `/`, `C:\`, or `\\` where 'C' can be A-Za-z. What I currently have is: 
`/^(\\(\\[^\s\\]+)+|([A-Za-z]:(\\)?|[A-z]:(\\[^\s\\]+)+))(\\)?$/`

Which works for finding paths like:
`\\a` `\\a\b\c\d\e\f` `C:\` `C:\a\b\c\d\e\f`

Now although I need a regex that can validate the way I currently have it ideally adding a rule for a forward slashed version as well like: `/a` and `/a/b/c/d/e/`

My actual question here is how to take what I have currently and alter it so I can find just `/`, `C:\`, or `\\` and report true on that only where 'C' can be A-Za-z. Helping out on both would be bonus though. As I am stuck and keep on breaking anything regex when I try to alter it myself. 