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inheritanceMystery

Author: Whitaker Brand

Assume that the following classes have been defined: 

public class Pen extends Sock {
    public void method1() {
        System.out.print("pen 1  ");
    }
}

public class Lamp {
    public void method1() {
        System.out.print("lamp 1  ");
    }
    
    public void method2() {
        System.out.print("lamp 2  ");
    }
    
    public String toString() {
        return "lamp";
    }
}

public class Book extends Sock {
    public void method2() {
        System.out.print("book 2  ");
        super.method2();
    }
}

public class Sock extends Lamp {
    public void method1() {
        System.out.print("sock 1  ");
        method2();
    }

    public String toString() {
        return "sock";
    }
}

Given the classes above, what output is produced by the following code? 

Lamp[] elements = {new Book(), new Pen(), new Lamp(), new Sock()};
for (int i = 0; i < elements.length; i++) {
    System.out.println(elements[i]);
    elements[i].method1();
    System.out.println();
    elements[i].method2();
    System.out.println();
    System.out.println();
}
elements[0]: Book
elements[1]: Pen
elements[2]: Lamp
elements[3]: Sock

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