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

void set_first(int values[3]) {
    static_assert(std::is_same<decltype(values), int*>::value, "adjusted");
    values[0] = 9;
}

template<class T, std::size_t N>
constexpr std::size_t count_of(const T (&)[N]) { return N; }

int main() {
    int values[3] = {1, 2, 3};
    static_assert(count_of(values) == 3, "bound retained");
    set_first(values);
    assert(values[0] == 9);
    std::cout << count_of(values) << ' ' << values[0] << '\n';
}