#include <experimental/generator> // MS VC++ /await /std=c++latest
#include <iostream>
#include <numeric>
#include <tuple>

using Triple = std::tuple<int, int, int>;
using namespace std::experimental;

generator<Triple> pythagorean_triples(int limit)
{
    for (auto z = 1; z < limit; ++z)
        for (auto y = 1; y < z; ++y)
            for (auto x = 1; x < y; ++x)
                if (x * x + y * y == z * z)
                {
                    std::cout << '\t' << x << ' ' << y << ' ' << z << '\n';
                    co_yield {x, y, z};
                }
}

generator<Triple> irreducible_pythagorean_triples(int limit)
{
    for (auto [x, y, z] : pythagorean_triples(limit))
        if (std::gcd(x, z) == 1 && std::gcd(y, z) == 1)
            co_yield {x, y, z};
}

int main()
{
    std::cout << "\tpythagorean triple\nirreducible\n";

    for (auto [x, y, z] : irreducible_pythagorean_triples(30))
        std::cout << x << ' ' << y << ' ' << z << '\n';
}