65 lines
2.2 KiB
C++
65 lines
2.2 KiB
C++
// fig10_46.cpp
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// Attempting to polymorphically call a function that is
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// inherited from each of two base classes.
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#include <iostream>
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// class Base definition
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class Base {
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public:
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virtual void print() const = 0; // pure virtual
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};
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// class DerivedOne definition
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class DerivedOne : public Base {
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public:
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// override print function
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void print() const override {std::cout << "DerivedOne\n";}
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};
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// class DerivedTwo definition
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class DerivedTwo : public Base {
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public:
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// override print function
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void print() const override {std::cout << "DerivedTwo\n";}
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};
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// class Multiple definition
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class Multiple : public DerivedOne, public DerivedTwo {
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public:
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// qualify which version of function print
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void print() const override {DerivedTwo::print();}
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};
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int main() {
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Multiple both{}; // instantiate a Multiple object
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DerivedOne one{}; // instantiate a DerivedOne object
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DerivedTwo two{}; // instantiate a DerivedTwo object
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Base* array[3]{}; // create array of base-class pointers
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array[0] = &both; // ERROR--ambiguous
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array[1] = &one;
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array[2] = &two;
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// polymorphically invoke print
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for (int i{0}; i < 3; ++i) {
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array[i] ->print();
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}
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}
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/**************************************************************************
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* (C) Copyright 1992-2022 by Deitel & Associates, Inc. and *
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* Pearson Education, Inc. All Rights Reserved. *
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* *
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* DISCLAIMER: The authors and publisher of this book have used their *
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* best efforts in preparing the book. These efforts include the *
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* development, research, and testing of the theories and programs *
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* to determine their effectiveness. The authors and publisher make *
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* no warranty of any kind, expressed or implied, with regard to these *
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* programs or to the documentation contained in these books. The authors *
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* and publisher shall not be liable in any event for incidental or *
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* consequential damages in connection with, or arising out of, the *
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* furnishing, performance, or use of these programs. *
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**************************************************************************/
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