The P and V operations on counting semaphores, where s is a counting semaphore, and defined as follows P(s): s = s 1; if s < 0 then wait; V(s): s = s + 1; if s < = 0 then we ke up a process waiting on s; Assume that Pb and Vb the wait and signal operations on binary semaphores are provided. Two binary semaphores Xb and Yb are used to implement the semaphore operations P(s) and V(s) as follows P(s): Pb (Xb); s = s 1; if (s < 0) { Vb (Xb); Pb (Yb); } else Vb (Xb); V(s): Pb (Yb); s = s + 1; if (s < = 0) Vb (Yb); Vb (Xb); The initial values of Xb and Yb are respectively

The P and V operations on counting semaphores, where s is a counting s

1.	The P and V operations on counting semaphores, where s is a counting semaphore, and defined as follows P(s): s = s 1; if s < 0 then wait; V(s): s = s + 1; if s < = 0 then we ke up a process waiting on s; Assume that Pb and Vb the wait and signal operations on binary semaphores are provided. Two binary semaphores Xb and Yb are used to implement the semaphore operations P(s) and V(s) as follows P(s): Pb (Xb); s = s 1; if (s < 0) { Vb (Xb); Pb (Yb); } else Vb (Xb); V(s): Pb (Yb); s = s + 1; if (s < = 0) Vb (Yb); Vb (Xb); The initial values of Xb and Yb are respectively
A.	0 and 0
B.	0 and 1
C.	1 and 0
D.	1 and 1
Answer» D. 1 and 1

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