C++ 继承_构造函数_析构函数

#include<iostream>
using namespace std;
class CExample
{
private:
    int a;
    int n;
public:
    //构造函数
    CExample(int b)
    {
        a=b;
        printf("constructor1 is called\n");
    }
    CExample(int c, int d)
    {
        a=c;
        printf("constructor2 is called\n");
    }
    CExample(int c, int d, int e)
    {
        a=c;
        printf("constructor2 is called\n");
    }
    //拷贝构造函数
    CExample(const CExample & c)
    {
        a=c.a;
        printf("copy constructor is called\n");
    }

    //析构函数
    ~CExample()
    {
        cout<<"destructor is called\n";
    }
    void show()
    {
        cout<<a<<endl;
    }
};
int main()
{
    CExample A(100);
    CExample B(12,24);
    A.show();
    B.show();
    return 0;
        //A.Show();
    //CExample B=A;
    //B.Show(); 
}