addrdedup

#!/usr/bin/env perl

use 5.22.0;
use warnings;

use Tie::IxHash;

# first line is meaningless?
my $first = <STDIN>;
my %hash;
tie %hash, 'Tie::IxHash';
while (<STDIN>) {
   my ($address, $rest) = split /\t/, $_, 2;
   $hash{$address} ||= ($rest||'');
}

print "\n";
print "$_\t$hash{$_}" for keys %hash;