#include <stdio.h>
#include <pthread.h>
#include <semaphore.h>
#include <sys/semaphore.h>

int counter = 0; // shared resource
sem_t semaphore; // semaphore declaration

void* increment(void* arg) {
    for (int i = 0; i < 100000; i++) {
        sem_wait(&semaphore); // lock
        counter++; // critical section
        sem_post(&semaphore); // unlock
    }
    return NULL;
}

int main() {
    pthread_t t1, t2;
    sem_init(&semaphore, 0, 1); // initialize semaphore with value 1

    pthread_create(&t1, NULL, increment, NULL);
    pthread_create(&t2, NULL, increment, NULL);
    pthread_join(t1, NULL);
    pthread_join(t2, NULL);

    sem_destroy(&semaphore);

    printf("Final Counter Value (with semaphores): %d\n", counter);

    return 0;
}