In your microflow:
- create an Integer variable called WeekCount
- use the following expression to set that variable parseInteger(substring(ColumnB,find(ColumnB,’ ‘)-1))
- Set the value of ColumnC with the following expression addWeeks(ColumnA,-1*$WeekCount)
Hope that helps you get started.
**EDIT**
my expression was wrong. I think it should be: parseInteger(substring(ColumnB,0,find(ColumnB,’ ‘)))