A>>int sum = 0;
A>>int a, b;

A>>void thread_fn()
A>>{
A>>  a = 3;
A>>  b = 1;

A>>  if (b == 1)
A>>    sum += a;
A>>}

A>>int main()
A>>{
A>>  thread t1(thread_fn);
A>>  thread t2(thread_fn);
A>>  t1.join();
A>>  t2.join();
A>>  return sum;
A>>}
A>>