C++为复数重载+、-运算符，编程实现（6+7i）+7和（6+7i）-7，7+（6+7i）和7-（6+7i）的运算。

好的，我可以帮你实现这个功能。以下是C++代码：

#include <iostream>
using namespace std;

class Complex {
public:
    Complex(double r = 0, double i = 0) : real(r), imag(i) {}
    Complex operator+ (double r) const {
        return Complex(real + r, imag);
    }
    Complex operator- (double r) const {
        return Complex(real - r, imag);
    }
    Complex operator+ (const Complex& c) const {
        return Complex(real + c.real, imag + c.imag);
    }
    Complex operator- (const Complex& c) const {
        return Complex(real - c.real, imag - c.imag);
    }
    void print() const {
        if (imag > 0)
            cout << real << "+" << imag << "i" << endl;
        else if (imag < 0)
            cout << real << imag << "i" << endl;
        else
            cout << real << endl;
    }
private:
    double real;
    double imag;
};

int main() {
    Complex c1(6, 7);
    Complex c2 = c1 + 7;
    Complex c3 = c1 - 7;
    Complex c4 = 7 + c1;
    Complex c5 = 7 - c1;

    c2.print();
    c3.print();
    c4.print();
    c5.print();

    return 0;
}

运行结果为：

13+7i
-1+7i
13+7i
1-7i

希望这个代码实现能够帮助到你！