#include <cassert>
#include <cstddef>
#include <iostream>
#include <type_traits>

template<class T>
T larger(T a, T b) { return a < b ? b : a; }
template<class T, std::size_t N>
constexpr std::size_t extent(const T (&)[N]) { return N; }

int main() {
    const int values[] = {2, 4, 6};
    static_assert(extent(values) == 3, "array extent survives");
    auto result = larger<double>(2, 3.5);
    static_assert(std::is_same<decltype(result), double>::value, "explicit type");
    assert(result == 3.5);
    assert(larger(2, 4) == 4);
    std::cout << extent(values) << ' ' << larger(2, 4) << '\n';
}