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polymorphismMystery3

Language/Type: C++ inheritance polymorphism

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

class Tongue : public Mouth {
public:
    virtual void m1() {
        cout << "T 1" << endl;
        Mouth::m1();
    }

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

class Nose : public Tongue {
public:
    virtual void m1() {
        cout << "N 1" << endl;
    }

    virtual void m2() {
        Tongue::m2();
        cout << "N 2" << endl;
    }

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

class Mouth {
public:
    virtual void m1() {
        cout << "M 1" << endl;
    }

    virtual void m2() {
        cout << "M 2" << endl;
        m1();
    }
};

class Ear : public Tongue {
public:
    virtual void m2() {
        m1();
        m1();
    }

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

Now assume that the following variables are defined: 

Mouth*  var1 = new Nose();
Tongue* var2 = new Ear();
Mouth*  var3 = new Tongue();
Tongue* var4 = new Nose();

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->m2();
var2->m2();
var2->m3();
var2->m4();
var4->m1();
var4->m3();
((Nose*) var1)->m2();
((Tongue*) var1)->m3();
((Ear*) var1)->m4();
((Nose*) var2)->m4();
((Tongue*) var3)->m1();
((Nose*) var4)->m3();

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