int-stream.cpp

#include <chrono>
#include <iostream>
#include <array>
#include <limits>
#include <functional>
#include <random>

template <typename T, std::size_t Size = (std::numeric_limits<T>::max() / 8) + 1>
class number_stack_check
{
    char* array_ = new char[Size];

public:
    const size_t size = Size;

    bool check(const T &value) {
        auto div = std::lldiv(value, 8);
        auto exists = array_[div.quot] & (1 << div.rem);
        array_[div.quot] |= (1 << div.rem);
        return exists;
    }
};

template <typename T>
void begin_test(const uint32_t &test_iteration_count = 10000)
{
    number_stack_check<T> c;
    std::cout << "Memory usage: " << c.size << std::endl;
    std::function<void(const T&)> call = [&c](const T &n){
        std::cout << std::boolalpha << "Check " << n << ":\t"
                  << c.check(n) << std::endl;
    };

    using lim = std::numeric_limits<T>;
    std::default_random_engine generator;
    std::uniform_int_distribution<int> random(lim::min(), lim::max());

    for (uint32_t i = 0; i < test_iteration_count; ++i) {
        call(random(generator));
    }
}

int main()
{
    begin_test<uint32_t>();
}