#!/usr/bin/perl
use warnings;
use strict;
use feature qw{ say };

my $LOAD_AT_ONCE = 500;

my $filename = shift;
open my $IN, '<', $filename or die $!;
my @part;

sub out {
    for my $i (0 .. $#{ $part[0] }) {
        open my $OUT, '>>', "$$.$i" or die $!;
        say {$OUT} join "\n", map $_->[$i], @part;
    }
    @part = ();
}

while (<$IN>) {
    push @part, [ split ' ' ];
    out() if @part == $LOAD_AT_ONCE;
    print STDERR "Phase 1: ", $IN->input_line_number, "\r";
}
out() if @part;

print STDERR "\n";

my @files = glob "$$.*";
seek $IN, 0, 0;
for my $i (0 .. $#files) {
    print STDERR "Phase 2: $i\r";
    open my $COL, '<', "$$.$i" or die $!;
    while (<$COL>) {
        chomp;
        last if $_ eq 'NA';
        print "$_ ";
    }
    my @rest = (split ' ', <$IN>)[ 1 + $i .. $#files ];
    say "@rest";
}

unlink glob "$$.*";