c++实现的一个MyArrayList

好的，下面是C++实现的一个MyArrayList，其中包含了常见的数组操作函数：

#include <iostream>
#include <stdexcept>

template <typename T>
class MyArrayList {
private:
    T *data;
    int size;
    int capacity;

public:
    MyArrayList(int capacity = 10) {
        this->capacity = capacity;
        data = new T[capacity];
        size = 0;
    }

    ~MyArrayList() {
        delete[] data;
    }

    int getSize() const {
        return size;
    }

    bool isEmpty() const {
        return size == 0;
    }

    void add(int index, T e) {
        if (index < 0 || index > size)
            throw std::invalid_argument("Add failed. Index is invalid.");

        if (size == capacity)
            resize(2 * capacity);

        for (int i = size - 1; i >= index; i--)
            data[i + 1] = data[i];

        data[index] = e;
        size++;
    }

    void addLast(T e) {
        add(size, e);
    }

    void addFirst(T e) {
        add(0, e);
    }

    T get(int index) const {
        if (index < 0 || index >= size)
            throw std::invalid_argument("Get failed. Index is invalid.");

        return data[index];
    }

    void set(int index, T e) {
        if (index < 0 || index >= size)
            throw std::invalid_argument("Set failed. Index is invalid.");

        data[index] = e;
    }

    bool contains(T e) const {
        for (int i = 0; i < size; i++) {
            if (data[i] == e)
                return true;
        }

        return false;
    }

    int find(T e) const {
        for (int i = 0; i < size; i++) {
            if (data[i] == e)
                return i;
        }

        return -1;
    }

    T remove(int index) {
        if (index < 0 || index >= size)
            throw std::invalid_argument("Remove failed. Index is invalid.");

        T ret = data[index];

        for (int i = index + 1; i < size; i++)
            data[i - 1] = data[i];

        size--;
        if (size == capacity / 4 && capacity / 2 != 0)
            resize(capacity / 2);

        return ret;
    }

    T removeFirst() {
        return remove(0);
    }

    T removeLast() {
        return remove(size - 1);
    }

    void removeElement(T e) {
        int index = find(e);
        if (index != -1)
            remove(index);
    }

private:
    void resize(int newCapacity) {
        T *newData = new T[newCapacity];
        for (int i = 0; i < size; i++)
            newData[i] = data[i];

        delete[] data;
        data = newData;
        capacity = newCapacity;
    }
};

int main() {
    MyArrayList<int> arr;

    for (int i = 0; i < 10; i++)
        arr.addLast(i);

    arr.add(1, 100);
    std::cout << arr.get(1) << std::endl;

    arr.remove(2);
    arr.removeElement(4);

    for (int i = 0; i < arr.getSize(); i++)
        std::cout << arr.get(i) << " ";
    std::cout << std::endl;

    return 0;
}

这个MyArrayList实现了动态扩展，可以在插入元素时自动扩容，也可以在删除元素时自动缩容。同时，还实现了常见的数组操作函数，例如在指定位置插入元素、在末尾添加元素、在头部添加元素、获取指定位置的元素、修改指定位置的元素、查找指定元素是否存在、查找指定元素的位置、删除指定位置的元素、删除第一个元素、删除最后一个元素、删除指定元素等。