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polymorphismMysteryHamburger

Language/Type: C++ inheritance polymorphism

Consider the following classes; assume that each is defined in its own file. 

class Hamburger : public Bacon {
public:
    virtual void m2() {
        cout << "H 2" << endl;
        Bacon::m2();
    }

    virtual void m4() {
        cout << "H 4" << endl;
    }
};

class Mayo : public Hamburger {
public:
    virtual void m3() {
        cout << "M 3" << endl;
        m1();
    }

    virtual void m4() {
        cout << "M 4" << endl;
    }
};

class Lettuce {
public:
    virtual void m1() {
        cout << "L 1" << endl;
        m2();
    }

    virtual void m2() {
        cout << "L 2" << endl;
    }
};

class Bacon : public Lettuce {
public:
    virtual void m1() {
        Lettuce::m1();
        cout << "B 1" << endl;
    }

    virtual void m3() {
        cout << "B 3" << endl;
    }
};

Now assume that the following variables are defined: 

Lettuce* var1 = new Bacon();
Bacon* var2 = new Mayo();
Lettuce* var3 = new Hamburger();
Bacon* var4 = new Hamburger();
Lettuce* var5 = new Lettuce();

In the table below, indicate in the right-hand column the output produced by the statement in the left-hand column. If the statement produces more than one line of output, indicate the line breaks with slashes as in "x / y / z" to indicate three lines of output with "x" followed by "y" followed by "z". If the statement does not compile, write "COMPILER ERROR". If a statement would crash at runtime or cause unpredictable behavior, write "CRASH".

var1->m1();
var1->m2();
var1->m3();
var2->m1();
var2->m2();
var2->m3();
var2->m4();
var3->m1();
var3->m2();
var4->m2();
var4->m3();
var4->m4();
((Bacon*) var1)->m1();
((Bacon*) var1)->m3();
((Mayo*) var5)->m3();
((Lettuce*) var4)->m3();
((Hamburger*)var2)->m4();
((Mayo*) var2)->m4();

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