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#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
#include <time.h>
#include <unistd.h>
int n;
pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
void*
fnO(void* arg)
{
int xrand;
int count = 0;
while (1) {
usleep(200 * 1000);
do {
xrand = rand();
} while ((xrand % 2) == 1);
count++;
pthread_mutex_lock(&mutex);
printf("Thread O, count = %d, old x = %d, x = %d, even = %d\n", count, n, n+xrand, ((n+xrand) % 2)==0);
n += xrand;
if ((count == 1000) || (count >= 10 && (n%2) == 0)) {
pthread_mutex_unlock(&mutex);
break;
}
pthread_mutex_unlock(&mutex);
}
printf("Thread O terminated.\n");
pthread_exit(NULL);
}
void*
fnE(void* arg)
{
int xrand;
int count = 0;
while (1) {
usleep(200 * 1000);
do {
xrand = rand();
} while ((xrand % 2) == 0);
count++;
pthread_mutex_lock(&mutex);
printf("\tThread E, count = %d, old x = %d, x = %d, odd = %d\n", count, n, n+xrand, ((n+xrand) % 2)==1);
n += xrand;
if ((count == 1000) || (count >= 10 && (n%2) == 1)) {
pthread_mutex_unlock(&mutex);
break;
}
pthread_mutex_unlock(&mutex);
}
printf("\tThread E terminated.\n");
pthread_exit(NULL);
}
int
main()
{
pthread_t tO, tE;
srand(time(NULL));
n = 0;
pthread_create(&tO, NULL, &fnO, NULL);
pthread_create(&tE, NULL, &fnE, NULL);
pthread_join(tO, NULL);
pthread_join(tE, NULL);
return 0;
}
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