#include <stdio.h>
#include <pthread.h>
 
#define NUM_THREADS 4
 
int shared = 0;
 
void *foo()
{
    for (int i = 0; i < 10000; ++i) {
        shared += 1;
    }
    return NULL;
}
 
int main()
{
    pthread_t threads[NUM_THREADS];
 
    for (int i = 0; i < NUM_THREADS; ++i) {
        pthread_create(&threads[i], NULL, foo, NULL);
    }
 
    for (int i = 0; i < NUM_THREADS; ++i) {
        pthread_join(threads[i], NULL);
    }
 
    printf("final result is %d\n", shared);
 
    return 0;
}

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