Question

I need to see if there are duplicates in an array of strings, what’s the most time-efficient way of doing it?

Answer 1

One of the things I love about Perl is it’s ability to almost read like English. It just sort of makes sense.

use strict;
use warnings;

my @array = qw/yes no maybe true false false perhaps no/;

my %seen;

foreach my $string (@array) {

    next unless $seen{$string}++;
    print "'$string' is duplicated.\n";
}

Output

'false' is duplicated.

'no' is duplicated.