#!/usr/bin/perl -w
print "Enter a list in /etc/passwd format : \n";
chomp(@input = <>);
foreach (@input)
{
   ($user, $name) = (split(/:/)) [0, 4];
   $name =~ s/[ ,\/](.*)//;
   $dup{$name} .= " $user";
}
foreach $key (keys %dup)
{
   if($dup{$key} =~ /. /)
   {
      $dup{$key} =~ s/^ //;
      print $dup{$key} . " have duplicate first names.\n"
   }
}