#include <atomic>
#include <cassert>
#include <iostream>

int main() {
    volatile int observed = 0;
    observed = 7;
    const int snapshot = observed;
    std::atomic<int> count{0};
    const int previous = count.fetch_add(1, std::memory_order_relaxed);
    assert(snapshot == 7);
    assert(previous == 0);
    assert(count.load(std::memory_order_relaxed) == 1);
    std::cout << snapshot << ' ' << count.load() << '\n';
}