71 lines
1.6 KiB
C++
71 lines
1.6 KiB
C++
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// rtti1.cpp -- using the RTTI dynamic_cast operator
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#include <iostream>
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#include <cstdlib>
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#include <ctime>
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using std::cout;
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class Grand
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{
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private:
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int hold;
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public:
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Grand(int h = 0) : hold(h) {}
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virtual void Speak() const { cout << "I am a grand class!\n";}
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virtual int Value() const { return hold; }
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};
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class Superb : public Grand
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{
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public:
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Superb(int h = 0) : Grand(h) {}
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void Speak() const {cout << "I am a superb class!!\n"; }
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virtual void Say() const
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{ cout << "I hold the superb value of " << Value() << "!\n";}
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};
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class Magnificent : public Superb
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{
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private:
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char ch;
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public:
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Magnificent(int h = 0, char c = 'A') : Superb(h), ch(c) {}
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void Speak() const {cout << "I am a magnificent class!!!\n";}
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void Say() const {cout << "I hold the character " << ch <<
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" and the integer " << Value() << "!\n"; }
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};
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Grand * GetOne();
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int main()
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{
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std::srand(std::time(0));
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Grand * pg;
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Superb * ps;
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for (int i = 0; i < 5; i++)
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{
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pg = GetOne();
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pg->Speak();
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if( ps = dynamic_cast<Superb *>(pg))
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ps->Say();
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}
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// std::cin.get();
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return 0;
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}
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Grand * GetOne() // generate one of three kinds of objects randomly
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{
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Grand * p;
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switch( std::rand() % 3)
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{
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case 0: p = new Grand(std::rand() % 100);
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break;
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case 1: p = new Superb(std::rand() % 100);
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break;
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case 2: p = new Magnificent(std::rand() % 100,
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'A' + std::rand() % 26);
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break;
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}
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return p;
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}
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