complex为表示复数的类,若以友元函数的形式重载“+”运算符以执行两个complex实例的相加操作,则此运算符重载函数在complex中的声明为
时间: 2024-02-13 08:05:18 浏览: 23
以下是在complex类中声明友元函数“+”运算符重载函数的示例代码:
```
class complex {
private:
double real;
double imag;
public:
complex(double r = 0, double i = 0): real(r), imag(i) {}
friend complex operator+(const complex& c1, const complex& c2);
};
complex operator+(const complex& c1, const complex& c2) {
return complex(c1.real + c2.real, c1.imag + c2.imag);
}
```
在上述代码中,声明了一个名为“operator+”、返回类型为“complex”的友元函数。通过在类定义中使用“friend”关键字,使得该函数能够访问该类中的私有成员。在函数定义中,使用两个const引用作为参数,分别表示要相加的两个complex实例。最后,返回一个新的complex实例,其实部为两个实例的实部相加,虚部为两个实例的虚部相加。
相关问题
编写程序实现 Complex 类,包含两个整数成员变量实部和虚部。 .友元函数实现++运算符重载;.成员函数实现﹣﹣运算符重载;.友元函数实现*运算符重载;.实现输入和输出运算符重载;
好的,我来为您编写一个 Complex 类实现以下功能:
1. 包含两个整数成员变量实部和虚部;
2. 友元函数实现++运算符重载;
3. 成员函数实现﹣﹣运算符重载;
4. 友元函数实现*运算符重载;
5. 实现输入和输出运算符重载。
代码如下:
```c++
#include <iostream>
using namespace std;
class Complex {
private:
int real; // 实部
int imag; // 虚部
public:
// 构造函数
Complex(int real = 0, int imag = 0) {
this->real = real;
this->imag = imag;
}
// 友元函数实现++运算符重载
friend Complex operator++(Complex &a, int) {
Complex old = a;
a.real++;
a.imag++;
return old;
}
// 成员函数实现﹣﹣运算符重载
Complex operator--() {
real--;
imag--;
return *this;
}
// 友元函数实现*运算符重载
friend Complex operator*(const Complex &a, const Complex &b) {
Complex c;
c.real = a.real * b.real - a.imag * b.imag;
c.imag = a.real * b.imag + a.imag * b.real;
return c;
}
// 实现输入和输出运算符重载
friend ostream& operator<<(ostream &out, const Complex &c) {
out << c.real << "+" << c.imag << "i";
return out;
}
friend istream& operator>>(istream &in, Complex &c) {
cout << "请输入实部和虚部,格式为:实部 虚部" << endl;
in >> c.real >> c.imag;
return in;
}
};
int main() {
Complex c1, c2;
cin >> c1 >> c2;
cout << "c1 = " << c1 << endl;
cout << "c2 = " << c2 << endl;
Complex c3 = c1 * c2;
cout << "c1 * c2 = " << c3 << endl;
cout << "c1++ = " << c1++ << endl;
cout << "--c2 = " << --c2 << endl;
return 0;
}
```
您可以在 `main()` 函数中进行测试,可以自行修改输入输出的值。
用C++设计一个complex类并用友元函数重载乘法运算符实现两复数的乘除法
好的,下面是实现代码:
```c++
#include <iostream>
using namespace std;
class complex {
private:
double real;
double imag;
public:
complex(double r = 0, double i = 0) : real(r), imag(i) {}
friend complex operator*(const complex &c1, const complex &c2);
friend complex operator/(const complex &c1, const complex &c2);
void print() {
cout << "(" << real << "," << imag << ")" << endl;
}
};
complex operator*(const complex &c1, const complex &c2) {
double r = c1.real * c2.real - c1.imag * c2.imag;
double i = c1.real * c2.imag + c1.imag * c2.real;
return complex(r, i);
}
complex operator/(const complex &c1, const complex &c2) {
double r = (c1.real * c2.real + c1.imag * c2.imag) / (c2.real * c2.real + c2.imag * c2.imag);
double i = (c1.imag * c2.real - c1.real * c2.imag) / (c2.real * c2.real + c2.imag * c2.imag);
return complex(r, i);
}
int main() {
complex c1(1, 2), c2(3, 4);
complex c3 = c1 * c2;
complex c4 = c1 / c2;
c3.print();
c4.print();
return 0;
}
```
解释一下:
- `complex` 类表示复数,有实部和虚部两个数据成员;
- 构造函数用于初始化实部和虚部;
- `operator*` 和 `operator/` 是友元函数,用来重载乘法和除法运算符;
- `print` 函数用于输出复数。
在 `main` 函数中,创建两个复数 `c1` 和 `c2`,并计算它们的积 `c3` 和商 `c4`,最后输出 `c3` 和 `c4`。