Select all of the following statements that are true 0 After the execution of the banker's algorithm, if Finish[i] == false for all processes i, then the system is in a safe state. The banker's algorithm can only be applied when there are single units of each resource type only. Unsafe system states can lead to deadlocks. Deadlock avoidance aims to ensure that a system of processes will never enter an unsafe state. Claim edges in resource allocation graphs indicate resource requests that a process may send out in the future. In order for the banker's algorithm to be applicable, when a process starts up, it must state in advance the maximum number of resources it may request in the

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OZ PROGRAMMING LANGUAGE    Exercise 1. (Efficient Recurrence Relations Calculation) At slide 54 of Lecture 10, we have seen aconcurrent implementation of classical Fibonacci recurrence. This is: fun {Fib X} if X==0 then 0 elseif X==1 then 1 else thread {Fib X-1} end + {Fib X-2} end end By calling Fib for actual parameter value 6, we get the following execution containing several calls ofthe same actual parameters.For example, F3, that stands for {Fib 3}, is calculated independently three times (although it providesthe same value every time). Write an efficient Oz implementation that is doing a function call for a givenactual parameter only once.Consider a more general recurrence relation, e.g.:F0, F1, ..., Fm-1 are known as initial values.Fn = g(Fn-1, ..., Fn-m), for any n ≥ m.For example, Fibonacci recurrence has m=2, g(x, y) = x+y, F0=F1=1

In the study of formal languages state-transition diagrams are often usedto visualize changes in a machine’s configuration as it acts on input. To visualize amachine’s configuration think of its parts: Commonly a finite set of states, a finiteinput alphabet Σ, Perhaps storage devices (a stack, input/output tapes). The states arepictured as named circles sometimes decorated with symbols to denote special states,e.g. start and final states. Changes in configuration are denoted by labeled edges andperhaps changes in storage.1. Describe how edges are labeled and their meaning for finite state machines.2. Describe how edges are labeled and their meaning for pushdown automata.3. Describe how edges are labeled and their meaning for Turing machines.