Suppose a building has 5 floors (1-5) which are occupied by officesThe ground floor (0) is not
used for business purposesEach floor has 80 people working on it, and there are 4 elevators
availableEach elevator can hold 10 people at one timeThe elevators take 3 seconds to travel
between floors and average 22 seconds on each floor when someone enters or exitsIf all of the
people arrive at work at about the same time and enter the elevators on the ground floor, how
should the elevators be used to get the people to their offices as quickly as possible?