Atomic Counter Without a Mutex

Difficulty

Asked at XTX Markets, Jump Trading

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Language: C++23StripedCounter

#include <algorithm>
#include <atomic>
#include <cstddef>
#include <memory>
#include <thread>
#include <tuple>
#include <utility>
#include <vector>

// ...
// ...
// ...
// ...
class StripedCounter {
public:
    explicit StripedCounter(std::size_t shardCount) {
        // ...
        // ...
        (void)shardCount;
    }

    void increment(std::size_t shardHint) {
        // ...
        (void)shardHint;
    }

    long long read() const {
        // ...
        return 0;
    }

    std::vector<long long> shardValues() const {
        // ...
        return {};
    }

private:
    // ...
};

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