#!perl -n
# llil2cmd.pl. Abbreviated version of llil2grt.pl.
chomp; ($w,$c) = split/\t/; $h{$w} += $c;
END {
   $\=$/;
   push @l, pack('NA*',-$v,"$k\t$v") while ($k,$v)=each %h;
   print substr($_,4) for sort @l;
}

##</code><code>##

> time perl llil2grt.pl big1.txt big2.txt big3.txt >grt1.tmp
llil2grt start
get_properties : 8 secs
sort + output  : 22 secs
total          : 30 secs

real    0m33.475s
user    0m32.180s
sys     0m1.295s

##</code><code>##

> time perl llil2cmd.pl big1.txt big2.txt big3.txt >cmd1.tmp

real    0m28.937s
user    0m27.843s
sys     0m1.093s

> diff cmd1.tmp grt1.tmp

##</code><code>##

#!perl -n
# llil2cmd-long.pl. A long short version of llil2grt.pl.
BEGIN {
   $tstart1 = time;
}
chomp; ($w,$c) = split/\t/; $h{$w} += $c;
END {
   my $tstart2 = time;
   $\=$/;
   push @l, pack('NA*',-$v,"$k\t$v") while ($k,$v)=each %h;
   print substr($_,4) for sort @l;
   my $tend2  = time;
   my $taken1 = $tstart2 - $tstart1;
   my $taken2 = $tend2   - $tstart2;
   my $taken  = $tend2   - $tstart1;
   warn "get_properties : $taken1 secs\n";
   warn "sort + output  : $taken2 secs\n";
   warn "total          : $taken secs\n";
}

##</code><code>##

$ time perl llil2cmd-long.pl big1.txt big2.txt big3.txt >long1.tmp
get_properties : 7 secs
sort + output  : 21 secs
total          : 28 secs

real    0m28.629s
user    0m27.707s
sys     0m0.917s

> diff long1.tmp grt1.tmp

##</code><code>##

wget https://www.cpan.org/src/5.0/perl-5.36.0.tar.gz
(update: run sha256sum perl-5.36.0.tar.gz and check matches https://www.cpan.org/src/5.0/perl-5.36.0.tar.gz.sha256.txt)
tar -xzf perl-5.36.0.tar.gz
cd perl-5.36.0
./Configure -des -Dprefix=$HOME/localperl
make 2>&1 | tee make.tmp
make test 2>&1 | tee test.tmp
make install 2>&1 | tee install.tmp

##</code><code>##

use 5.036;
use experimental qw/for_list declared_refs/;

##</code><code>##

while (my ($k, $v) = each %{$href}) { push @lines, pack('NA*', -$v, "$k\t$v") }

##</code><code>##

for my ($k, $v) (%{$href}) { push @lines, pack('NA*', -$v, "$k\t$v") }

##</code><code>##

$ cd $HOME/localperlmodules
$ type perl
perl is hashed ($HOME/localperl/bin/perl)
$ wget https://www.cpan.org/modules/by-module/Roman/Roman-1.24.tar.gz
$ tar -xzf Roman-1.24.tar.gz
$ cd Roman-1.24
$ perl Makefile.PL 2>&1 | tee make.tmp
$ make 2>&1 | tee make.tmp
$ make test 2>&1 | tee test.tmp
$ make install 2>&1 | tee install.tmp