33 lines
1006 B
C++
33 lines
1006 B
C++
#include <iostream>
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class Human {
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public:
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Human() { std::cout << "Human constructor\n"; }
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};
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// The virutal keyword tells the compiler:
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// "Hey, if this class is used in a diamond-like hierarchy, only one shared Human base should exist, no matter how many paths lead to it."
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// The compiler then: Makes sure that only one instance of Human exists inside CSStudent.
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class Student : virtual public Human {
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public:
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Student() { std::cout << "Student constructor\n"; }
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};
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class Worker : virtual public Human {
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public:
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Worker() { std::cout << "Worker constructor\n"; }
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};
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class CSStudent : public Student, public Worker {
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public:
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CSStudent() { std::cout << "CSStudent constructor\n"; }
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};
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// problem with this program: Human constructor runs twice!
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int main() {
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// CSStudent has two copies of Human, one via Student and one via Worker.
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// Ambiguity: If we try to access a Human member from CSStudent, the compiler doesn’t know which one we mean.
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CSStudent cs;
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return 0;
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}
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