Uh, not quite. You'll be throwing away any false key ("", "0").

You want: 

my @common = grep exists $hash2{$_}, keys %hash1;
my @unique1 = grep !exists $hash2{$_}, keys %hash1;
my @unique2 = grep !exists $hash1{$_}, keys %hash2;

[download]
But if you really want all three at once: 
my %t;
$t{$_} .= "1" for keys %hash1;
$t{$_} .= "2" for keys %hash2;

[download]
And then each element of %t will be "1" for 1 only, "2" for 2 only, or "12" for both.

-- Randal L. Schwartz, Perl hacker
Be sure to read my standard disclaimer if this is a reply.

In reply to •Re: Re: Hash table question by merlyn
in thread Hash table question by fiddler42

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