#include <iostream>

int& foo() {
    int a = 10;
    return a;
}

void decay_to_pointer(int arr[3]) {
    std::cout << "array decays to pointer: " << sizeof(arr) << std::endl;
}

void pass_by_reference(int (&arr)[3]) {
    std::cout << "array passed to function by reference: " << sizeof(arr) << std::endl;
}

int main() {
    int b = 10;
    double c = 4.5;

    double* dptr;
    // dptr = &b // compile error
    dptr = reinterpret_cast<double*>(&b);
    std::cout << "before b: " << b << std::endl;
    std::cout << "before *dptr: " << *dptr << std::endl; // 이상한 주소를 가리키게 됨
    *dptr += 1;
    std::cout << "before b: " << b << std::endl;
    std::cout << "before *dptr: " << *dptr << std::endl;

    std::cout << std::endl;

    int* iptr;
    // iptr = &c; // compile error
    iptr = reinterpret_cast<int*>(&c);
    std::cout << "before c: " << c << std::endl;
    std::cout << "before iptr: " << *iptr << std::endl; // 이상한 주소를 가리키게 됨
    *iptr += 2;
    std::cout << "before c: " << c << std::endl;
    std::cout << "before iptr: " << *iptr << std::endl;
    std::cout << std::endl;

    int* dang_p;
    // int* dang_p = 10; // rvalue assign -> compile error
    // *dang_p = 10; // runtime error
    int& dang_r = foo();

    // std::cout << *dang_p << std::endl; // runtime error
    // std::cout << dang_r << std::endl; // runtime error

    int arr[3] = {0,};
    decay_to_pointer(arr);
    pass_by_reference(arr);
}