Here's my implementation -
use strict;
use Data::Dumper;

chomp(my @files = <DATA>);

# find unique basenames
my @basenames = keys %{{ map { (split/\./)[0] => 1 } @files }};

# find unpaired files
foreach my $basename (@basenames) {
    my @matches = grep (/$basename/, @files);
    print "$matches[0]\n" if $#matches == 0;
}

__DATA__
00000001.did
00000001.mrg
00000002.did
00000002.mrg
00000003.did
00000004.mrg

[download]
And the output -
00000004.mrg
00000003.did

[download]

In reply to Re: Finding un-paired files in a directory by Roger
in thread Finding un-paired files in a directory by inman

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