I have the cust_id's and region fields.As per the requirement.One custid is available multiple regions.
Logic we have to build is how we can show the distinct custid's region wise.Please find the attached sample app.
In the app we no need show the custid as dimension and we have to show the count of distinct custid's as 4.(we have to count any one of the custid.E.g 1001 is available in NORTH1 AND NORTH2 so we have to count in any one of the region and same logic for 42424 as well.
Let me know if in case of any concerns.It will help to do the logic in front end level.