Power Query , Use distinct list of values as Row Headers

Hi,
I've attahed a workbook showing in excel what I'd like to acheive in power query,

I have done this in power query but it is not usable as I had to use Table.Disctinct, and in most cases this would not be the case,

In excel I have a column and each cell contains, eg;
a,b a,b,c d,a e,f

and I would like to have a new column with a row for each distinct item.

in excel ;

Please Login or Register  to view this content.

and for the values

Please Login or Register  to view this content.

But this part is secondary and I'd just like to get a column added.

Richard

Thanks, that's really good, I had a go with pivoting but had not thought of using the 'rows' .
RD

I used List Accumulate to get the final X , null ;

First took TableColumnNames of Pivot table Names =

Please Login or Register  to view this content.

and then ;

Please Login or Register  to view this content.

RD

Thanks, wonderful idea, will be keeping that for future reference.

RD