**Concepts:**

V(S): Signal will increment the semaphore variable, that is, S++.

P(S): Signal will decrement the semaphore variable., that is, S--.

**Data:**

Initial counting semaphore = x

Signal operation = 12 V

Wait operation = 20 P

Since at least 1 process in blocked state

Final counting semaphore (F) = -1

**Formula:**

F ≥ x + 20P + 12V

**Calculation:**

-1 ≥ x + 20(-1) + 12(+1)

**∴**** x ≤ 7 **

Therefore, largest value of initial semaphore count is 7