# use hash keys to hold unique id codes
my %id_codes;

# number of codes to generate
my $batch_qty = 100;

# length of id code
my $length = 24;

while (scalar keys(%id_codes) < $batch_qty){
	my $id;
	for (1..$length){
        $id .= ('A'..'Z', 'a'..'z', '0'..'9')[rand(62)];
	}
	$id_codes{$id} = 1;
}