#!/usr/bin/env perl

use strict;
use warnings;
use List::Util 1.45 qw(uniq);

my $char_at=10;
my $num_chars=50;
open my $fh, '<:encoding(UTF-8)', $ARGV[0]
    or die "Could not open '$ARGV[0]' $!";
my @trnAccounts;
while (my $line = <$fh>) {
    chomp $line;
    next unless $line && length($line) >= $char_at;
    push @trnAccounts, substr($line, $char_at, $num_chars);
}

my @unique_accounts = uniq(@trnAccounts);
for my $i (0..$#unique_accounts) {
    print $i, ":", $unique_accounts[$i], "\n";
}
print "total: ", scalar(@trnAccounts), "\n";
print "uniq : ", scalar(@unique_accounts), "\n";