I want a Perl program to quit when a user enters the word, "badword". Therefore I have the following conditional: 

if($input =~ /badword/i){exit 1;}

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This works for most users, but some clever users have bypassed the conditional by submitting strings such as "bad.word", "b.a.d.w.o.r.d", "b/a/d/w/o/r/d" and "b a.d*w/o r-d".

So, my question is:

How can I modify my conditional statement so that if a user enters the string "badword" with ANY non-alphanumeric characters in between each letter, then the program quits?

Thank you so much.

In reply to prohibiting certain strings by keiusui

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