45 lines
706 B
C++
45 lines
706 B
C++
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// 构造函数的分类与调用
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#include <iostream>
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using namespace std;
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class B
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{
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private:
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int n;
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public:
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// B() { cout << "B()" << endl; }
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B(int n)
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{
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cout << "B(int n)" << endl;
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this->n = n;
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}
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B(const B &other)
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{
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cout << "B(B &other)" << endl;
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this->n = other.n;
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}
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public:
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void showN()
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{
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cout << "n = " << n << endl;
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}
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};
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int main()
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{
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B b1 = 20; // 隐式调用 B(int n), B(20), 只创建一个对象
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B b2 = B(30); // 显式调用 B(int n)
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B b3 = b2; // 隐式调用 B(B &other)
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B &b4 = b3; // 不会创建空间，只是一个别名
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B b5(b4); // 显式调用 B(B &other)
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return 0;
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}
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