Calculating Conflict equivalent schedule in Transaction Management

The lectures of transaction management system which consists of 40 videos, in part 20 I haven't understood why you decide 4! By 2! * 2!. Plz clear my doubt. Thank you.

Rishi Yadav @rishiyadav
12 Sep 2017 01:25 pm

In permutation and Combinations

If there are n objects if one type n1 objects and n2 type another objects 


(Total objects) n=n1+n2 

so permutation will be n! by n1! * n2!