iOS生产者消费者问题

    //生产者消费者
    dispatch_semaphore_t semaphore = dispatch_semaphore_create(1);
    NSMutableArray *array = [[NSMutableArray alloc] init];
    dispatch_queue_t queue = dispatch_queue_create("cn.chutong.www", DISPATCH_QUEUE_CONCURRENT);
    int max_count = 10000;
    //生产
    dispatch_async(queue, ^{
        while (YES) {
            if (array.count >= max_count) {
                dispatch_semaphore_wait(semaphore, DISPATCH_TIME_FOREVER);
            }
            int count = random()%10;
            sleep(0.05f);
            [array addObject:[NSString stringWithFormat:@"%d",count]];
//            dispatch_semaphore_signal(semaphore);
            NSLog(@"生产了%d",count);
        }
    });
    //消费
    dispatch_async(queue, ^{
        while (YES) {
            if (array.count>=max_count) {
                NSLog(@"消费了%ld", array.count);
//                dispatch_semaphore_wait(semaphore, DISPATCH_TIME_FOREVER);
//                [array removeLastObject];
                [array removeAllObjects];
                dispatch_semaphore_signal(semaphore);
            }

        }
    });