#!/usr/bin/perl

use warnings;
use strict;

open(FILE2,">file1.txt")|| die "Could not open: $!\n";

open(FILE3,"file2.txt")|| die "Could not open: $!\n";
my @data = <FILE3>;
close(FILE3); 

my %hash;
    
foreach my $_data (@data) 
{
    my $computer_name = (split(/\t/, $_data))[0];

    if (! exists($hash{$computer_name}))
    {
        $hash{$computer_name} = undef;
        print FILE2 $_data;
    }

}
             
close(FILE2);