42 lines
720 B
C++
42 lines
720 B
C++
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// 向上类型转换
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#include <iostream>
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#include <cstring>
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#include <cstdlib>
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using namespace std;
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class Printer
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{
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public:
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void open()
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{
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cout << "打印机正在开机..." << endl;
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}
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};
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class DellPrinter : public Printer
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{
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void open()
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{
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cout << "Dell打印机..." << endl;
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}
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};
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class HuaweiPrinter : public Printer
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{
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void open()
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{
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cout << "Huawei打印机..." << endl;
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}
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};
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int main()
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{
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DellPrinter dellprinter;
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// 多态: 通过父类的引用或指针调用子类对象的成员
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// 子类对象自动向上转换位父类的类型
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Printer &printer = dellprinter;
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printer.open(); // 输出: 打印机正在开机...
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return 0;
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}
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