static int sum_stat_a = 0;
static int sum_stat_b = 0;
int aggregateStats(int stat_a, int stat_b) {
    pthread_mutex_lock(&mut);
    //wait for other thread to finish
        while (sum_stat_a == 0 && sum_stat_b == 0){
            pthread_cond_wait(&cond, &condlock);
        }
        pthread_mutex_unlock(&condlock);
        pthread_mutex_lock(&mut);

    sum_stat_a += stat_a;
    sum_stat_b += stat_b;
    return sum_stat_a + sum_stat_b;

        pthread_mutex_unlock(&mut);

}
void init(void)
{
    pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
    pthread_mutex_t condlock;
    pthread_mutex_t mut;
    pthread_mutex_init(&condlock, NULL);
    pthread_mutex_init(&mut, NULL);
}