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

sem_t can_produce;
sem_t can_consume;

void *producer(void *data) {
    while (1) {
        sem_wait(&can_produce);
        puts("PRODUCING!");
        sem_post(&can_consume);
    }
}

void *consumer(void *data) {
    while (1) {
        sem_wait(&can_consume);
        puts("CONSUMING!");
        sem_post(&can_produce);
    }
}

int main(int argc, char **argv) {
    pthread_t thread_prod, thread_cons;

    sem_init(&can_produce, 0, 1);
    sem_init(&can_consume, 0, 0);

    pthread_create(&thread_prod, NULL, producer, NULL);
    pthread_create(&thread_cons, NULL, consumer, NULL);

    pthread_join(thread_cons, NULL);
    pthread_join(thread_prod, NULL);

    return 0;
}