C++ でテンプレートと汎用プログラミング機能を実装するにはどうすればよいですか?

#include <iostream>

// 模板函数的定义
template <typename T>
T Max(T a, T b) {
    return (a > b) ? a : b;
}

int main() {
    int num1 = 10;
    int num2 = 15;
    std::cout << "Max of " << num1 << " and " << num2 << " is: " << Max(num1, num2) << std::endl;

    double num3 = 3.14;
    double num4 = 2.71;
    std::cout << "Max of " << num3 << " and " << num4 << " is: " << Max(num3, num4) << std::endl;

    return 0;
}

#include <iostream>

// 模板类的定义
template <typename T>
class Stack {
private:
    T* data;  // 用于存储数据的数组
    int size;  // 栈的大小
    int top;  // 栈顶的索引

public:
    // 构造函数，对栈进行初始化
    Stack(int stackSize) {
        size = stackSize;
        data = new T[size];
        top = -1;
    }

    // 析构函数，释放内存
    ~Stack() {
        delete[] data;
    }

    // 入栈操作
    void Push(T val) {
        if (top == size - 1) {
            std::cout << "Stack is full!" << std::endl;
            return;
        }
        data[++top] = val;
    }

    // 出栈操作
    T Pop() {
        if (top == -1) {
            std::cout << "Stack is empty!" << std::endl;
            return T();
        }
        return data[top--];
    }

    // 获取栈顶元素
    T Top() {
        if (top == -1) {
            std::cout << "Stack is empty!" << std::endl;
            return T();
        }
        return data[top];
    }
};

int main() {
    Stack<int> intStack(3);
    intStack.Push(1);
    intStack.Push(2);
    intStack.Push(3);

    std::cout << "Top element: " << intStack.Top() << std::endl;
    std::cout << "Popped element: " << intStack.Pop() << std::endl;
    std::cout << "Popped element: " << intStack.Pop() << std::endl;
    std::cout << "Top element: " << intStack.Top() << std::endl;

    Stack<double> doubleStack(3);
    doubleStack.Push(1.23);
    doubleStack.Push(4.56);

    std::cout << "Top element: " << doubleStack.Top() << std::endl;
    std::cout << "Popped element: " << doubleStack.Pop() << std::endl;
    std::cout << "Top element: " << doubleStack.Top() << std::endl;

    return 0;
}

#include <iostream>
#include <vector>

// 快速排序的模板函数
template <typename T>
void QuickSort(std::vector<T>& arr, int left, int right) {
    if (left < right) {
        int i = left, j = right;
        T pivot = arr[left];

        while (i < j) {
            while (i < j && arr[j] > pivot) {
                j--;
            }
            if (i < j) {
                arr[i++] = arr[j];
            }

            while (i < j && arr[i] <= pivot) {
                i++;
            }
            if (i < j) {
                arr[j--] = arr[i];
            }
        }

        arr[i] = pivot;
        QuickSort(arr, left, i - 1);
        QuickSort(arr, i + 1, right);
    }
}

int main() {
    std::vector<int> arr {5, 2, 7, 1, 9, 3};
    QuickSort(arr, 0, arr.size() - 1);

    for (const auto& num : arr) {
        std::cout << num << " ";
    }
    std::cout << std::endl;

    return 0;
}