Bank Semaphore project.

For this project, we will be simulating a bank, having some number of tellers. Each customer arrives at the bank, waits in a single line until a teller becomes free, and then goes to that teller to transact his/her business, leaving the bank when his/her business is done. In this case, a thread simulates each individual customer. The major parameters of this system are: the number of tellers, the rate at which new customers arrive (specified as an average interval between arrivals), and the average time it takes to service a customer. If (average inter-arrival time) = (average service time) / (# of tellers) then the system will eventually reach a steady state with a fairly constant waiting line length. The value for each of these three parameters supplied to the assignment’s program should be chosen to satisfy the above so the tellers are productive and the customers don’t become angry. Therefore, to test your program, choose values for two of the parameters in the equation of the above and then compute the value of the third parameter. You can generate several different sets of values for the three parameters to test your program. For this project, you write a program that simulates this system. At startup, your program will accept the three parameters mentioned above plus the length of time to run the simulation. All times will be entered in seconds. To avoid having to run the program for an entire day, we will simulate ten seconds of "simulated world" time by one second of actual program run time. The simulation will proceed as follows: 1. One thread will be responsible for creating new customers at random intervals, such that the average time between new customers is equal to the specified parameter. It will exist throughout the simulation. 2. Created when a customer arrives, a unique thread simulates each customer, works its way through the bank, and then terminates. 3. A general semaphore that uses a FIFO queue will simulate the waiting line. 4. The semaphore initializes to the number of tellers. If there are n tellers, then the first n customers doing an acquire() on this semaphore will be able to proceed without delay. 5. When each customer thread enters the bank, he/she will do a acquire() on this semaphore. When he/she finishes being served, he/she will do a release(), allowing another customer to pass the semaphore and use the teller.