If you just want a specific one, then jettero's solution is good. If you anticipate many of these lookups, creating a reverse hash may be useful. 
my %reverse;
push @{ $reverse{ $sandwichHash{$_} } }, $_ for keys %sandwichHash;

print "@{ $reverse{'burger'} }\n";
print "@{ $reverse{'panini'} }\n";
print "@{ $reverse{'hoagie'} }\n";

[download]
My criteria for good software:
  1. Does it work?
  2. Can someone else come in, make a change, and be reasonably certain no bugs were introduced?

In reply to Re: One to many hash question by dragonchild
in thread One to many hash question by BengalsRock

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