3.1 Declare an integer array of rank 3 which might be suitable for
representing a hotel with 3 buildings, each with 8 floors and 16 rooms
on each floor, and write an assignment of the value 3 to the 5th room on
floor 7 of the second building.

Answer:

    INTEGER, DIMENSION(3,8,16) :: rooms

    rooms(2,7,5) = 3