#!/usr/bin/perl -W

my $alluids = "/tmp/uid_list.file";

open (UIDS, ">$alluids") || die "Cannot open file $alluids\n";

while (my @uidlst = getpwent) {
    print UIDS "$uidlst[2]\n";
}

close(UIDS);

open (UIDS, "<$alluids") || die "Cannot open file $alluids\n";
while(<UIDS>) {
  chomp;
  push(@arr, $_);
}
close(UIDS);

my %hash = map { $_ => 1 } @arr;
foreach $i (200..250) {
if ( ! defined $hash{$i} ) {
print "$i ";
}
}