#include <iostream>
#include <algorithm>
#include <vector>
 
bool increase(std::size_t size, std::vector<std::size_t>& it)
{
    for (std::size_t i = 0, size = it.size(); i != size; ++i) {
        const std::size_t index = size - 1 - i;
        ++it[index];
        if (it[index] > size) {
            it[index] = 0;
        } else {
            return true;
        }
    }
    return false;
}
 
template <typename F, typename T>
void self_cartesian_product(F&& f, const std::vector<T>& v, std::size_t N)
{
    std::vector<std::size_t> it(N, 0);
 
    do {
        f(v, it);
    } while (increase(v.size(), it));
}
 
 
int main()
{
    self_cartesian_product([](const auto& v, const auto& indexes)
         {
             for (auto i : indexes) {
                 std::cout << v[i] << " ";
             }
             std::cout << std::endl;
         },
         std::vector<int>{-2, -1, 0, 1, 2},
         3);
}
 

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