Operating System Consider the following semaphore-based solution to the readers-writers problem: Common initialization section for both writer and reader: semaphore wrt=1, mutex=1; int readcount=0; The code bodies for writer and reader ( P() and V() are equivalent to wait() and signal() ): a) Fill in the underlined areas in the above code in Reader() to make it a complete solution to the readers-writers problem. Your solution should allow multiple concurrent readers, but only one writer, to access the shared database simultaneously. (8 pts) b) Suppose a writer thread is inside its critical section performing writing, while another writer and n>1 readers are waiting outside their critical sections. Which semaphores are they waiting on, respectively? (6 pts) c) Does this solution give preference to waiting readers or waiting writers? Why? (6 pts)