#include <iostream>
#include <thread>
#include <vector>
 
int main() {
    int shared_counter = 0;
 
    std::vector<std::thread> threads;
    for (int i = 0; i < 4; ++i) {
        threads.emplace_back([&](int id) {
            for (int j = 0; j < 1000; ++j) {
                ++shared_counter;  // Race here: load, increment, store not atomic
            }
            std::cout << "Thread " << id << " finished.\n";
        }, i);
    }
 
    for (auto& t : threads) t.join();
    std::cout << "Final counter: " << shared_counter << " (expect <4000 due to races)\n";
    return 0;
}

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