#include <iostream>
#include <string>

using namespace std;

int & Foo(int &);
//int & Bar(int);

int main() {
    int a{99};

    // must initialize when declared.
    int &b{a};

    cout << "After Initialization " << endl;
    cout << " a = " << a  << endl;
    cout << " b = " << b  << endl;
    cout << " &a = " << &a << endl;
    cout << " &b = " << &b << endl;
    cout << endl << endl;

    cout << "Setting b to be -100 " << endl;
    b = -100;
    cout << " a = " << a  << endl;
    cout << " b = " << b  << endl;
    cout << endl << endl;

    cout << "Setting a to be 42 " << endl;
    a = 42;
    cout << " a = " << a  << endl;
    cout << " b = " << b  << endl;
    cout << endl << endl;

    int & works = Foo(a);
    cout << "Works is " << works << endl;
    cout << " &a     = " << &a << endl;
    cout << " &works = " << &works << endl;

/*
    cout << "We will now have a bug " << endl;
    int & bad = Bar(3);

    cout << "Bad holds " << bad << endl;
*/

    return 0;
}

int & Foo(int & x){
    return x ;
}

/*
int & Bar(int x){
    int y{x};

    return y ;
}
*/