以交错方式打印小字母和大写字母

Question

我有两个字母数组。一个是小写字母，另一个是大写字母，如下所示。

char arr1[] = "abcdefghijklmnopqrstuvwxyz";
char arr2[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";

我想运行两个线程（POSIX）来获取输出，如下所示。

aAbBcCdDeEfFgGhHiIjJkKlLmMnNoOpPqQrRsStTuUvVwWxXyYzZ.

Answer 1

void * print_message_function1（void * ptr）;

void * print_message_function2（void * ptr）;

sem_t s1，s2;

int main（） {

 pthread_t thread1, thread2;
 const char *message1 = "abcdefghijklmnopqrstuvwxyz";
 const char *message2 = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
 int  iret1, iret2;

 sem_init(&s1, 0, 0);
 sem_init(&s2, 0, 0);

 pthread_create( &thread1, NULL, print_message_function1, (void*) message1);


pthread_create( &thread2, NULL, print_message_function2, (void*) message2);


 pthread_join( thread1, NULL);
 pthread_join( thread2, NULL);
 sem_destroy(&s1);
 sem_destroy(&s2);

 return 0;

}

void * print_message_function1（void * ptr） {

 char *message;
 message = (char *) ptr;
 while(*message != '\0')
 {
 printf("%c ", *message++);
 sem_wait(&s2);
 sem_post(&s1);

 }

}

void * print_message_function2（void * ptr） {

 char *message;
 message = (char *) ptr;
 while(*message != '\0')
 {
 printf("%c ", *message++);
 sem_post(&s2);
 sem_wait(&s1);
 }

}