#!/usr/bin/perl

use strict;
use warnings;

open my $FH1,"<", "file1.txt" or die "could not open file1.txt: $!";
open my $FH2,"<", "file2.txt" or die "could not open file2.txt: $!";

my @array=<$FH2>;

while (my $line1 = <$FH1>) {
        my @hold;
        my @coll = split /\s+/, $line1;

        my $hit=$coll[5];
        @hold = grep /$hit/, @array;
        my $held = shift @hold;
   
        if (defined $held) {
                my @cols = split /\s+/, $held;
                print join "\t", @cols;
                print "\n";
        }
        else{
                print join "\t", @coll;
                print "\n";
        }
}

##</code><code>##

my %lines;

read_results("file1.txt");
read_results("file2.txt");

print "$lines{$_}\n" for sort {$a <=> $b} keys %lines;

sub read_results {
    my $fn = shift;

    open my $FH, "<", $fn or die "couldn't open $fn: $!";

    while (my $line = <$FH>) {
        chomp $line;
        my ($id) = $line =~ /TAT_(\d+)/;
        next unless $id;
        $lines{$id} = $line;
    }
}