Print in Order

<-E 1114> Print in Order

class Foo {
public:
    Foo() {
        pthread_mutex_lock(&m_second);
        pthread_mutex_lock(&m_third);
    }
    
    ~Foo() {
        pthread_mutex_destroy(&m_second);
        pthread_mutex_destroy(&m_third);
    }

    void first(function<void()> printFirst) {
        
        // printFirst() outputs "first". Do not change or remove this line.
        printFirst();
        pthread_mutex_unlock(&m_second);
    }

    void second(function<void()> printSecond) {
        
        // printSecond() outputs "second". Do not change or remove this line.
        pthread_mutex_lock(&m_second);
        printSecond();
        pthread_mutex_unlock(&m_third);
    }

    void third(function<void()> printThird) {
        
        // printThird() outputs "third". Do not change or remove this line.
        pthread_mutex_lock(&m_third);
        printThird();
    }
private:
    pthread_mutex_t m_second = PTHREAD_MUTEX_INITIALIZER;
    pthread_mutex_t m_third = PTHREAD_MUTEX_INITIALIZER;
};