Factorial:

Produce a program that will ask the user for two integers, x and y, and display all the factorials from x to y.  Also display the sum of the factorials:

***************
   FACTORIAL
***************

Enter two integers: 3 9

The factorials from 3 to 9 are:
3! = 6
4! = 24
5! = 120
6! = 720
7! = 5040
8! = 40320
9! = 362880


The factorials from 9 to 3 are:
9! = 362880
8! = 40320
7! = 5040
6! = 720
5! = 120
4! = 24
3! = 6

The sum of the factorials is:
6 + 362880 = 362886