Networkdays - excluding weekend and custom list of dates

I am trying to figure out simple way of calculating number of days between two dates excluding the weekend (Saturday and Sunday) and excluding a list of custom dates
So lets say we have start date 12/01/2018 and end date 12/05/2018 (mm/dd/yyyy) and we have in our custom date list 12/04/2018 that needs to be excluded - the formula should consider the weekend and all the custom dates that are between start and end date and calculate the difference - in this example we have first and second December weekend days and 1 custom date - so the result should be 2

A1 = start date
A2 = end date
A3 = RESULT


B1:B10 = list of custom dates to be excluded from counting the difference between A1 and A2