And if you want to know where in the array the element exists, try this find routine:

use strict;

my @a = qw/aaa bbc dde fff dde www/;
my $e = 'dde';
print join(',', find($e, @a)), "\n";

sub find {
  my ($target, @array) = @_;
  grep {$array[$_] eq $target} (0 .. @array - 1)
}
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which, in this example, returns:

2,4
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