面向对象——案例练习（3）判断两个立方体是否相等

利用全局函数实现

#define _CRT_SECURE_NO_WARNINGS
#include <iostream>

using namespace std;

class Cube
{
public:
    void setABC(int a, int b, int c)
    {
        m_a = a;
        m_b = b;
        m_c = c;
    }
    int getArea()
    {
        return ((m_a*m_b) + (m_b*m_c) + (m_a*m_c)) * 2;
    }

    int getVolume()
    {
        return m_a*m_b*m_c;
    }

    int getA()
    {
        return m_a;
    }

    int getB()
    {
        return m_b;
    }

    int getC()
    {
        return m_c;
    }
private:
    int m_a;
    int m_b;
    int m_c;
};

//全局函数
bool judgeCube(Cube &c1, Cube &c2)
{
    if (c1.getA() == c2.getA() && 
        c1.getB() == c2.getB() && 
        c1.getC() == c2.getC())
    {
        return true;
    }
    else
    {
        return false;
    }

}

int main(void)
{
    Cube c1;
    c1.setABC(10, 20, 30);

    Cube c2;
    c2.setABC(10, 20, 30);

    cout << "c1的体积是：" << c1.getVolume() << endl;
    cout << "c1的面积是：" << c2.getArea() << endl;

    if (judgeCube(c1, c2) == true)
    {
        cout << "相等" << endl;
    }
    else 
    {
        cout << "不相等" << endl;
    }

    return 0;
}

利用成员函数实现：

#define _CRT_SECURE_NO_WARNINGS
#include <iostream>

using namespace std;

class Cube
{
public:
    void setABC(int a, int b, int c)
    {
        m_a = a;
        m_b = b;
        m_c = c;
    }
    int getArea()
    {
        return ((m_a*m_b) + (m_b*m_c) + (m_a*m_c)) * 2;
    }

    int getVolume()
    {
        return m_a*m_b*m_c;
    }

    int getA()
    {
        return m_a;
    }

    int getB()
    {
        return m_b;
    }

    int getC()
    {
        return m_c;
    }
　　//同类之间无私处
    bool judgeCube(Cube &another)
    {
        if (m_a == another.m_a &&
            m_b == another.m_b &&
            m_c == another.m_c)
        {
            return true;
        }
        else
        {
            return false;
        }
    }

private:
    int m_a;
    int m_b;
    int m_c;
};

int main(void)
{
    Cube c1;
    c1.setABC(10, 20, 30);

    Cube c2;
    c2.setABC(10, 20, 30);

    cout << "c1的体积是：" << c1.getVolume() << endl;
    cout << "c1的面积是：" << c2.getArea() << endl;

    if (c1.judgeCube(c2) == true)
    {
        cout << "相等" << endl;
    }
    else
    {
        cout << "不相等" << endl;
    }

    return 0;
}