use strict;
use warnings;
use Data::Dumper;

my @data_array = (
        [qw/14 27 999 999 0 0/],
        [qw/14 27 999 999 0 0/],
        [qw/14 27 999 999 0 0/],
        [qw/14 27 999 999 1 0/],
        [qw/14 27 999 999 0 0/],
        [qw/14 27 999 999 0 0/],
        [qw/14 27 999 999 0 0/],
        [qw/27 14 999 999 0 0/],
        [qw/20 32 999 999 0 0/],
        [qw/20 32 999 999 0 0/],
        [qw/20 32 999 999 0 0/],
        [qw/20 32 999 999 1 0/],
        [qw/20 32 999 999 0 0/],
        [qw/20 32 999 999 0 0/],
        [qw/20 32 999 999 0 0/]
);

my @array = map { $_->[4] ? () : join(' ', sort @{$_}[0,1]) } @data_array;

my %freq;
$freq{$_}++ for @array;

my @final = map { "$_ $freq{$_}" } keys %freq;

print Dumper(\@final);