拷贝构造函数的相关

拷贝构造函数参数应该为引用，拷贝构造函数的参数使用引用类型不是为了减少一次内存拷贝， 而是避免拷贝构造函数无限制的递归下去。

#include<iostream>using namespace std;class A {private:    int value;public:    A(int n) {        value = n;        cout << value;        cout << "带参构造"<<endl;    }    A(const A &other) {        value = other.value;        cout << value;        cout << "拷贝构造"<<endl;    }    A &operator=(const A &other) {        value = other.value;        cout << value;        cout << "赋值运算符重载" << endl;        return *this;    }    void print(A other) {        cout << value << endl;    }};int main(void) {    A a(10);    A c(20);    c = a;    A b = a;    b.print(b);    c.print(c);    system("pause");    return 0;}