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

pthread_mutex_t bilangan_lock = PTHREAD_MUTEX_INITIALIZER;
int bilangan = 0;
pthread_t T0;

void *tambah(void *a) {
    int i, j;
    pthread_mutex_lock(&bilangan_lock);
    for (i = 0; i < 20; i++)
    {
       j = bilangan;
       j++;
       sleep(1);
       bilangan = j;
    }
    pthread_mutex_unlock(&bilangan_lock);
    return NULL;
}

int main() {
    int i, j;
    printf("nilai bilangan Awal = %i\n", bilangan);
    if (pthread_create(&T0, NULL, tambah, NULL) == -1) 
        perror("thread tidak bisa dibuat");
    pthread_mutex_lock(&bilangan_lock);
    for (i = 0; i < 20; i++)
    {
       j = bilangan;
       j++;
       sleep(1);
       bilangan = j;
    }
    pthread_mutex_unlock(&bilangan_lock);
    void* result;
    pthread_join(T0, &result);
    printf("nilai bilangan Akhir = %i\n", bilangan);
    return 0;
}