A system is composed of four processes, p1 through p4, and three types of resources, R1 through R3. There is one unit each of R1 and R3 available.
a. p1 requests a unit of R1 and a unit of R3.
b. p2 produces a unit of R1 and a unit of R3 and requests one unit of R2.
c. p3 requests a unit of R1 and a unit of R3. . d. p4 produces a unit of R2 and requests one unit of R3.
Show the resource allocation graph to represent the system state. Which, if any, of the processes are deadlocked in this state? Identify the processes in the cycle if deadlocked. Otherwise show any safe sequence of execution.