C++中常见的代码复用问题解决方案

#include <iOStream>
using namespace std;

int square(int num) {
    return num * num;
}

int main() {
    int num;
    cout << "请输入一个数：";
    cin >> num;
    cout << "平方是：" << square(num) << endl;
    return 0;
}

#include <iostream>
using namespace std;

template<typename T>
T max(T a, T b) {
    return (a > b) ? a : b;
}

int main() {
    int num1 = 10, num2 = 20;
    cout << "较大的数是：" << max(num1, num2) << endl;

    double num3 = 3.14, num4 = 2.71;
    cout << "较大的数是：" << max(num3, num4) << endl;

    return 0;
}

#include <iostream>
using namespace std;

class Shape {
public:
    virtual double CalculateArea() {
        return 0;
    }
};

class Rectangle : public Shape {
private:
    double width, height;
public:
    Rectangle(double w, double h) {
        width = w;
        height = h;
    }

    double CalculateArea() {
        return width * height;
    }
};

int main() {
    Shape* shape = new Rectangle(5, 6);
    cout << "矩形的面积是：" << shape->CalculateArea() << endl;
    delete shape;

    return 0;
}