Programming :: Implementing Sleeping Barber's With Multiple Barbers?

I'm working on a problem in which i have to implement the regular sleeping barber problem with multiple (say n) barbers. The code i'm using is this :

#include<stdio.h>
#include<stdlib.h>
#include<unistd.h>
#include<pthread.h>
#include<errno.h>
#include<sys/ipc.h>
#include<semaphore.h>
[Code]...

how to implement the modification? (there are many more such modifications where i'm stuck , but will ask about those later)