Hi all.
I'm hoping someone can point out the error of my ways... I'm sure there is a simple regex for this but I'm buggered if I can figure it out.

I am trying to match a field that may have a number of leading spaces, followed by a number of digits, but can't have any spaces after a digit has been found. It must contain at least one digit at the end,
i.e. valid data may be
'     999' or '   9999' or '9999999' '      9'.

but can't be

'  99  9'.

I have a regex which works

\S{7}|\s{6}\d{1}|\s{5}\d{2}|\s{4}\d{3}|\s{3}\d{4}|\s{2}\d{5}|\s{1}\d{6
+}|\d{7}

[download]
but when you're checking a 16 byte filed

ZZZZZZZZZZZZ9V99

a regex of 

(\s{12}\d{1}|\s{11}\d{2}|\s{10}\d{3}|\s{9}\d{4}|\s{8}\d{5}|\s{7}\d{6}|
+\s{6}\d{7}|\s{5}\d{8}|\s{4}\d{9}|\s{3}\d
{10}|\s{2}\d{11}|\s{1}\d{12}|\d{13})\.\d{2}

[download]
whilst doing the job,is getting ludicrously large and unreadable

There must be a shorter regex that covers this?

Someone at work suggested using an sprintf in it's stead within the regex, but I must be honest and say that suggestion has left me clueless on how to do it.

Thanks for your time

In reply to Should be a simple spaces/digits regex....but I'm turning grey! by viffer

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