使用运算符重载添加两个向量

Question

我有一个 class Vectors 有私有动态数组。我只想添加两个 Vectors 对象，例如 A = A + B，但程序一直崩溃。

这是我的声明 class:

class Vectors
    {
    private:
        int* vector;
    public:
        Vectors(int);
        Vectors(Vectors&);
        ~Vectors();

        Vectors operator+(Vectors&);

    };

这是我的实现：

#include "Vectors.h"
#include "iostream"
using namespace std;

Vectors::Vectors(int value)
{
    this->vector = new int[3];
    for (auto i = 0; i < 3; i++)
    {
        vector[i] = 3;
    }
}

Vectors::Vectors(Vectorsy& copy)
{
    this->vector = new int[3];
    for (auto i = 0; i < 3; i++)
    {
        vector[i] = copy.vector[i];
    }
}

Vectors::~Vectors()
{
    delete[] vector;
}

Vectors Vectors::operator+(Vectors& obj) // There is sth wrong here.
{
    for (auto i = 0; i < 3; i++)
        this->vector[i] += obj.vector[i];

    return *this;
}

这是我得到的错误：

Answer 1

我相信您需要一个 operator= 函数。你还没有实现它，所以编译器写了一个默认的，它做了错误的事情（因为 class 有一个指针）。很可能是在两次删除同一内存时发生崩溃。

见What is The Rule of Three?

Answer 2

问题是复制构造函数 (Vectors::Vectors(const Vectors& copy) 听到工作代码。

#include "iostream"
using namespace std;

class Vectors
    {
    private:
        int* vector;
    public:
        Vectors(int);
        Vectors(const Vectors&);
        ~Vectors();

        Vectors operator+(Vectors&);

    };


Vectors::Vectors(int value)
{
    this->vector = new int[3];
    for (auto i = 0; i < 3; i++)
    {
        vector[i] = 3;
    }
}

Vectors::Vectors(const Vectors& copy)
{
    this->vector = new int[3];
    for (auto i = 0; i < 3; i++)
    {
        vector[i] = copy.vector[i];
    }
}

Vectors::~Vectors()
{
    delete[] vector;
}

Vectors Vectors::operator+(Vectors& obj) // There is sth wrong here.
{
    for (auto i = 0; i < 3; i++)
        this->vector[i] += obj.vector[i];

    return *this;
}

int main()
{
        Vectors A(3), B(3);
        Vectors C = A+B;
}

使用运算符重载添加两个向量

Adding two vectors using operator overloading

c++

operator-overloading