#include <cassert>
#include <iostream>

struct Base { virtual ~Base() = default; };
struct Derived : Base { int value = 7; };
struct Other : Base {};

int main() {
    Derived object;
    Base* base = &object;
    Derived* derived = dynamic_cast<Derived*>(base);
    assert(derived != nullptr && derived->value == 7);
    assert(dynamic_cast<Other*>(base) == nullptr);
    int editable = 3;
    const int* read_only = &editable;
    *const_cast<int*>(read_only) = 4;
    const int whole = static_cast<int>(3.75);
    assert(editable == 4 && whole == 3);
    std::cout << derived->value << ' ' << editable << ' ' << whole << '\n';
}