#!/usr/bin/perl -w

open(IN, "< UinIN.txt") or die "Can't open file: $!";
open(OUT, "+> UinOut.txt") or die "Can't open file out.txt for writing: $!";

@input = <IN>;
close(IN);
%seen = ();

foreach $item (@input)
{
  unless ($seen{$item})
  {
    $seen{$item} = 1;
    print OUT $item;
  }
}
close(OUT);