sicp exercise 3.49

;; Exercise 3.49.  Give a scenario where the deadlock-avoidance mechanism described above does not work. (Hint: In the exchange problem, each process knows in advance which accounts it will need to get access to. Consider a situation where a process must get access to some shared resources before it can know which additional shared resources it will require.)

;; Ans: If the resources are not acquired in order, there is always a chance of deadlock.