C7-2 多继承
(100/100 分数)
题目描述
下面的代码声明了三个基类Base1、Base2和Base3,然后从这三个基类按照公有方式派生出类Derived。在每个类中分别定义带一个整型参数的构造函数和析构函数输出提示信息,构造函数的提示信息中需要包含整型参数的数值。请将下面的代码补充完整,使得输出结果与样例输出相同,注意:测试数据有多组。
#include <iostream> using namespace std; class Base1 { public: Base1(int x); ~Base1(); }; class Base2 { public: Base2(int x); ~Base2(); }; class Base3 { public: Base3(int x); ~Base3(); }; class Derived://继承上面3个类 { public: Derived(int x1, int x2, int x3, int x4); ~Derived(); }; Base1::Base1(int x) { cout<<"Base1 constructor called "<<x<<endl; } Base1::~Base1() { cout<<"Base1 destructor called"<<endl; } //依照Base1类中的代码实现其它类的构造函数和析构函数 int main() { int x[4]; for (int i = 0; i < 4; ++i) cin >> x[i]; Derived d(x[0], x[1], x[2], x[3]); return 0; }
输入描述
每组输入为 4 个整数用空格隔开
输出描述
根据构造和析构函数的调用顺序输出
样例输入
1 2 3 4
样例输出
Base2 constructor called 3 Base1 constructor called 2 Base3 constructor called 4 Derived constructor called 1 Derived destructor called Base3 destructor called Base1 destructor called Base2 destructor called
这个题目有一点坑,从输出来看创建的顺序是2,1,3,销毁的顺序是3,1,2说明继承的时候的顺序一定是2,1,3
#include <iostream>
using namespace std;
class Base1
{
public:
Base1(int x);
~Base1();
};
class Base2
{
public:
Base2(int x);
~Base2();
};
class Base3
{
public:
Base3(int x);
~Base3();
};
class Derived :public Base2, Base1, Base3//继承上面3个类
{
public:
Derived(int x1, int x2, int x3, int x4);
~Derived();
};
Base1::Base1(int x)
{
cout << "Base1 constructor called " << x << endl;
}
Base1::~Base1()
{
cout << "Base1 destructor called" << endl;
}
//依照Base1类中的代码实现其它类的构造函数和析构函数
Base2::Base2(int x)
{
cout << "Base2 constructor called " << x << endl;
}
Base2::~Base2()
{
cout << "Base2 destructor called" << endl;
}
Base3::Base3(int x)
{
cout << "Base3 constructor called " << x << endl;
}
Base3::~Base3()
{
cout << "Base3 destructor called" << endl;
}
Derived::Derived(int x1, int x2, int x3, int x4) :Base1(x2),Base2(x3),Base3(x4)
{
cout << "Derived constructor called " << x1 << endl;
}
Derived::~Derived()
{
cout << "Derived destructor called " << endl;
}
int main()
{
int x[4];
for (int i = 0; i < 4; ++i)
cin >> x[i];
Derived d(x[0], x[1], x[2], x[3]);
return 0;
}