Suppose a computer center has two printers, A and B, that are similar but not identical. Three kinds of processes use the printers: those that must use A, those that must use B, and those that can use either A or B.

Develop a monitor to allocate the printers, and show the code that the processes execute to request and release a printer. Your solution should be fair, assuming that printers are eventually released (that is, you do not have to worry about processes that request a printer and then never return it). Use the Signal and Continue discipline.