#include <cassert>
#include <iostream>

int main() {
    int value = 3;
    const int& read_only = value;
    value = 7;
    assert(read_only == 7);
    int* const fixed_pointer = &value;
    *fixed_pointer = 9;
    const int* read_pointer = &value;
    assert(*read_pointer == 9);
    constexpr int limit = 10;
    static_assert(limit > 0, "positive limit");
    std::cout << read_only << ' ' << limit << '\n';
}