Because exists checks for the existence of keys and not values. Instead a grep might be better suited e.g 
my @array = qw/ foo bar baz quux /;
my %hash  = qw/ f1  baz f2  foo  /;
my @newarray;

foreach my $thing (@array)   {
   push @newarray, $thing
     if grep { $_ eq $thing } values %hash;
}

print "newarray - @newarray\n";

__output__

newarray - foo baz

[download]
This isn't terrifically optimal so you may want to create another hash where the values are the keys (although the solution starts to look like finding an array intersection which is another option).
HTH

_________
broquaint

In reply to Re: hashes - finding values by broquaint
in thread hashes - finding values by Anonymous Monk

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