重载包含多个对象的加法操作符c++

Question

我需要重载多个不同对象的加法运算符并返回一个‘群集对象：“重载加法运算符(+)以添加台式机、膝上型计算机和集群的任何实例组合。这个操作符应该返回一个类型为群集的对象”因此，如果我有desktop1+laptop1+laptop2，我需要它返回一个集群，该集群可以添加所有内存和每个对象的其他变量。但是它只会添加所有对象从计算机类继承的变量。下面是我的项目其余部分的代码。谢谢！

#include <iostream>

using namespace std;

class computer
{
    public:
        double RAM;
        double CPUSpeed;
        int numberOfCores;
        double HDDSize;
        virtual void print();
};
class desktop : public computer
{
    public:
        bool hasMonitor;
        double monitorSize;
        friend istream& operator>> (istream &in, desktop &myDesktop);
};
class laptop : public computer
{
    public:
        double screenSize;
};
class cluster : public computer
{
    public:
        int numOfComp;
};
desktop::desktop()
{
    RAM = 0;
    CPUSpeed = 0;
    numberOfCores = 0;
    HDDSize = 0;
    hasMonitor = 0;
    monitorSize = 0;
}
laptop::laptop()
{
    RAM = 0;
    CPUSpeed = 0;
    numberOfCores = 0;
    HDDSize = 0;
    screenSize = 0;
}
cluster::cluster()
{
    RAM = 0;
    CPUSpeed = 0;
    numberOfCores = 0;
    HDDSize = 0;
    numOfComp = 0;
}
istream& operator>> (istream &in, desktop &myDesktop)
{
    in >> myDesktop.hasMonitor;
    in >> myDesktop.monitorSize;
    in >> myDesktop.RAM;
    in >> myDesktop.CPUSpeed;
    in >> myDesktop.HDDSize;
    in >> myDesktop.numberOfCores;
    return in;
}
istream& operator>> (istream &in, laptop &mylaptop)
{
    in >> mylaptop.RAM;
    in >> mylaptop.CPUSpeed;
    in >> mylaptop.HDDSize;
    in >> mylaptop.numberOfCores;
    in >> mylaptop.screenSize;
    return in;
}
istream& operator>> (istream &in, cluster &myCluster)
{
    in >> myCluster.RAM;
    in >> myCluster.CPUSpeed;
    in >> myCluster.HDDSize;
    in >> myCluster.numberOfCores;
    in >> myCluster.numOfComp;
    return in;
}
operator+(computer &myComp)
{
    return 

Answer 1

如果只想将它们从计算机继承的所有类的公共值相加，可以这样做：

cluster operator+(const computer& comp1, const computer& comp2)
{
    cluster ret;
    ret.RAM = comp1.RAM+comp2.RAM;
    ret.CPUSpeed = comp1.CPUSpeed+comp2.CPUSpeed;
    ret.numberOfCores = comp1.numberOfCores+comp2.numberOfCores;
    ret.HDDSize = comp1.HDDSize+comp2.HDDSize;
    return ret;
}

int main()
{
    laptop laptop1;
    desktop desktop1;
    desktop desktop2;
    cluster mycluster = laptop1+desktop1+desktop2;
    return 0;
}

链式+运算符是从右向左计算的。该函数返回一个群集对象，然后该对象可用作下一个加法的右手操作数。