#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

#define N 20
#define PROD 5
#define CONS 5
#define PROD_MAX 500

int shared_buffer[N];

void* producteur(void* args) {
    int j, product = 0;
    int count = 0;
    while (1) {
        int i = -1;
        while (++i < N) {
            if (shared_buffer[i] == -1) {
                break;
            }
        }
        if (i >= N) {
            sleep(0.05);
            continue;
        }
        product = (rand()%500+product)%20000;
        j = (i+j)%20000;
        shared_buffer[i] = product;
        count++;
        if (!(count % 5000))
            printf("produit: %d %d\n", j, product);
        sleep(0.05);
    }
    return NULL;
}

void* consommateur(void* args) {
    int j, product = 0;
    int count = 0;
    while (1) {
        int i = -1;
        while (++i < N) {
            if (shared_buffer[i] != -1) {
                break;
            }
        }
        if (i >= N) {
            sleep(0.05);
            continue;
        }
        product = (shared_buffer[i]+product)%20000;
        j = (i+j)%20000;
        shared_buffer[i] = -1;
        count++;
        if (!(count %5000))
            printf("résultat: %d %d %d\n", j, product);
        sleep(0.05);
    }
    return NULL;
}



int main() {
    for (int i=0; i < N; i++) {
        shared_buffer[i] = -1;
    }
    
    pthread_t tid[PROD+CONS];
    for (int i=0; i < PROD; i++) {
        pthread_create(&(tid[i]), NULL, &producteur, NULL);
    }

    for (int i=0; i < CONS; i++) {
        pthread_create(&(tid[i+PROD]), NULL, &consommateur, NULL);
    }

    for (int i=0; i < PROD+CONS; i++) {
        pthread_join(tid[i], NULL);
    }

    return 0;
}