多继承

代码示例

#include "iostream"

using namespace std;

class base1
{
public:
    base1() {}
    base1(int a, int b) : a(a), b(b) {}
    int a;

protected:
    int b;
};

class base2
{
public:
    base2() {}
    base2(int a, int b) : c(a), d(b) {}
    int c;

protected:
    int d;
};

class step : public base1, public base2
{

public:
    step(int a, int b) : base1(a, b), base2(a, b)
    {
    }
    void show878()
    {
        cout << a << endl;
        cout << b << endl;
        cout << c << endl;
        cout << d << endl;
    }
};

int main()
{
    base1 xy1(1, 2);
    base2 xy2(3, 4);
    step xy3(10, 20);
    xy3.show878();
}

多级继承

代码示例

#include "iostream"
using namespace std;

class base
{
public:
    void show1()
    {
        cout << "base" << endl;
    }
};

class step1 : public ::base
{
public:
    void show2()
    {
        cout << "step1" << endl;
    }
};

class step2 : public ::step1
{
public:
    void show3()
    {
        cout << "step2" << endl;
    }
};

int main()
{
    step2 rlxy;
    rlxy.show1();
    rlxy.show2();
    rlxy.show3();
}