Code reviewMediumcr-g580

Subject Concurrency non atomic counterLevel Mid–Senior~26 minCommon in Concurrency interviewsIndustries Software development, Technology

Question

Review this C++ worker-pool counter.

What a strong answer looks like

Separate real bugs from style. Rank issues by severity, point at the root cause rather than the symptom, and suggest a concrete fix — specific and kind.

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Code to reviewcpp

1#include <thread>2#include <vector>3#include <iostream>4 5long counter = 0;6 7void work(int iters) {8    for (int i = 0; i < iters; ++i) counter++;9}10 11int main() {12    std::vector<std::thread> ts;13    for (int t = 0; t < 8; ++t) ts.emplace_back(work, 1000000);14    for (auto& th : ts) th.join();15    std::cout << counter << "\n"; // expect 800000016    return 0;17}

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