sort {length $columnA <=> length $columnB} keys %dic; where do $columnA and $columnB come from? If you print $regex; do you get the expected result (an actually sorted list of alternatives?).

If you don't give us a fully working exemple we can only guess blindly. See How do I post a question effectively?

And to give us your input data, you can do something like:

use Data::Dumper;
# Code to fill %dic
print Dumper \%dic;
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