Re. your map solution, I think it might be safer to test for the existence of a key in case the value is 0 or the empty string. Also grep could come into play.

print
   map  { qq{$_ matches. It's values are $csahash{$_} and $cathhash{$_
+}\n} }
   grep { exists $cathhash{$_} }
   keys %csahash;

[download]

I hope this is of interest.

Cheers,

JohnGG

In reply to Re^2: hash question by johngg
in thread hash question by ada

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