I have a rather large hash as such:

%hash{'key1'}{'key2'}='string'

I need to find key2 when string eq $1 from a previous regex. I would like to avoid another foreach because this hash can have over 1000 key1's and it is already nested inside 4 foreach loops.

That said, any solution is welcome, even with the foreach loops.

I have experimented a bit with grep but it seems to only work on arrays. I also had an idea to print the hash into a long string and then regex or grep it but it never led anywhere.

Update: my hash is 1:1 and I use this structure extensively and need to do this lookup just once. Using the reverse function did exactly what I needed. Thanks all.

In reply to fast hash search by ddoc

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