#include <iostream>

#include <boost/thread/mutex.hpp>

#include <boost/thread/shared_mutex.hpp>

#include <boost/thread/lock_algorithms.hpp>

#include <boost/thread/thread_only.hpp>

#if defined BOOST_THREAD_DONT_USE_CHRONO

#include <boost/chrono/chrono_io.hpp>

#endif

#include <cassert>

#include <vector>

#define EXCLUSIVE 1

#define SHARED 2

#define MODE SHARED

class A

};

A::A(const A& a)

}

A&

A::operator=(const A& a)

{

if (this != &a)

{

boost::unique_lock<mutex_type> lk1(mut_, boost::defer_lock);

#if MODE == EXCLUSIVE

boost::unique_lock<mutex_type> lk2(a.mut_, boost::defer_lock);

#elif MODE == SHARED

boost::shared_lock<mutex_type> lk2(a.mut_, boost::defer_lock);

#else

#error MODE not set

#endif

boost::lock(lk1, lk2);

data_ = a.data_;

}

return *this;

}

A::compute(const A& x, const A& y)

}

A a1;

A a2;

void test_s()

}

void test_w()

}

int main()

}