my %seen;
while (<>) {
   my ($key) = /^(\S+)/;
   push @{ $seen{$key} }, $_;
}

for my $key (keys(%seen)) {
   my $vals = $seen{$key};
   print @$vals if @$vals > 1;
}

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In reply to Re: find duplicates and write to file by ikegami
in thread find duplicates and write to file by suhailck

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