// This example uses a non-standard simplified thread composition
// syntax. Triple braces enclose a list of threads with triple bar
// separating each thread.
int main() {
  atomic_int x;
  {{{ { x.store(1,mo_relaxed);
        x.store(2,mo_relaxed);
        x.store(4,mo_relaxed); }
  ||| { atomic_compare_exchange_weak_explicit(&x, 2, 3, mo_relaxed, mo_relaxed); } }}}
  return 0; }