| [[nodiscard]] static unsigned int hardware_concurrency() noexcept; | (since C++20) | 
Returns the number of concurrent threads supported by the implementation. The value should be considered only a hint.
(none).
Number of concurrent threads supported. If the value is not well defined or not computable, returns 0.
#include <iostream>
#include <thread>
 
int main() {
    unsigned int n = std::jthread::hardware_concurrency();
    std::cout << n << " concurrent threads are supported.\n";
}Possible output:
4 concurrent threads are supported.
| (C++17) | min offset to avoid false sharing max offset to promote true sharing (constant) | 
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