C++实现简易Vector类

用C++实现了一下简易的Vector类，主要是回忆起来练习下C++的模板类以及模板函数的使用。

参数博文：https://blog.csdn.net/happy_lucky52/article/details/76167125

主要实现了Vector的各个构造函数，Vector的常见操作。

博主水平堪忧，代码可能有Bug。

Vector.h

#pragma once
#include<iostream>
#include<cassert>
#include<algorithm>
using namespace std;

const int DEAULT_CAPACITY = 5;

template<typename T>
class Vector {
public:
    //各种构造函数和析构函数 
    Vector(int cap = DEAULT_CAPACITY, int sz = 0, const T v = T()) :
        capacity(cap), size(sz) {
        data = new T[capacity];
        for (int i = 0; i < size; i++) data[i] = v;
    }
    Vector(const T *arr, int n) {
        size = n;
        capacity = n;
        data = new T[capacity];
        for (int i = 0; i < size; i++) data[i] = arr[i];
    }
    Vector(const T *arr, int l, int r);
    Vector(const Vector<T> &v) {
        size = v.size;
        capacity = v.capacity;
        data = new T[capacity];
        for (int i = 0; i < size; i++) data[i] = v.data[i];
    }
    Vector(const Vector<T> &v, int l, int r) {
        size = r - l;
        capacity = size;
        data = new T[capacity];
        for (int i = 0; i < size; i++) data[i] = v.data[i + l];
    }
    ~Vector() { delete[] data; }
    Vector<T>& operator = (const Vector<T> &v);

    //获取信息 
    int GetCapacity() const { return capacity; }
    int GetSize() const { return size; }
    bool empty() const { return (size == 0); }
    int find(const T &v) const;

    //改变元素 
    void insert(int p, const T &v);
    void remove(int p);
    void CopyFrom(const T *v, int l, int r);
    void push_back(const T &v);
    void pop_back();
    void clear();
    void sort();

    //重载运算符
    /*T& operator [] (const int p) {
        assert(p >= 0 && p < size);
        return data[p];
    }*/
    template<typename T>
    friend ostream& operator << (ostream &o, const Vector<T> &v);

private:
    void expand();
    static void swap(T &a, T &b) { T tmp = a; a = b; b = tmp; }

protected:
    int capacity;    //容量 
    int size;        //Vector大小 
    T *data;        //实际数据 
};

template<typename T>
ostream& operator << (ostream &o, const Vector<T> &v) {
    for (int i = 0; i < v.GetSize(); i++)
        o << v.data[i] << " ";
    return o;
}

template<typename T>
Vector<T>& Vector<T>::operator= (const Vector<T> &v) {
    if (data == v.data) return *this;
    delete[]data;
    size = v.size;
    capacity = v.capacity;
    data = new T[v.capacity];
    CopyFrom(v.data, 0, size);
}

template<typename T>
void Vector<T>::CopyFrom(const T *v, int l, int r) {
    size = 0;
    for (int i = l; i < r; i++)
        data[size++] = v[i];
}

template<typename T>
void Vector<T>::expand() {
    if (size == capacity) {
        T *OldData = data;
        if (capacity < DEAULT_CAPACITY) capacity = DEAULT_CAPACITY;        //防止capacity为0时候出错
        capacity <<= 1;
        data = new T[capacity];
        CopyFrom(OldData, 0, size);
        delete[] OldData;
    }
}

template<typename T>
void Vector<T>::insert(int p, const T& v) {
    assert(p >= 0 && p <= size);
    expand();
    for (int i = size - 1; i >= p; i--) data[i + 1] = data[i];
    data[p] = v;
    size++;
}

template<typename T>
void Vector<T>::push_back(const T &v) {
    insert(size, v);
}

template<typename T>
void Vector<T>::remove(int p) {
    for (int i = p; i < size-1; i++)
        data[i] = data[i + 1];
    size--;
}

template<typename T>
void Vector<T>::pop_back() {
    assert(size > 0);
    remove(size - 1);
}

template<typename T>
void Vector<T>::clear() {
    while (size) pop_back();
}

template<typename T>
int Vector<T>::find(const T &p) const {
    for (int i = 0; i < size; i++)
        if (p == data[i]) return i;
    return -1;
}

template<typename T>
void Vector<T>::sort() {
    std::sort(data, data + size);
}

Test.cpp

#include "pch.h"
#include"Vector.h"
#include <iostream>
using namespace std;

//测试各种Vector操作
void Test1() {
    Vector<int> v1;
    v1.push_back(1);
    v1.push_back(2);
    v1.push_back(3);
    v1.push_back(4);
    cout << v1 << endl;
    v1.pop_back();
    cout << v1.GetSize() << endl;
    v1.push_back(1);
    cout << v1 << endl;
    cout << v1.find(1) << endl;
    v1.remove(v1.find(1));
    cout << v1 << endl;
    v1.push_back(55); v1.push_back(66);
    cout << v1.GetCapacity() << " " << v1.GetSize() << " " << v1 << endl;
    v1.push_back(77);
    cout << v1.GetCapacity() << " " << v1.GetSize() << " " << v1 << endl;
    v1.clear();
    cout << v1.GetSize()<<" "<<v1 << endl;
}
//测试不同的构造函数
void Test2() {
    Vector<int> v2(5, 5, 2);
    cout << v2.GetCapacity() << " " << v2.GetSize() << " " << v2 << endl;
    Vector<int> v3(v2);
    v3.push_back(61);
    cout << v3.GetCapacity() << " " << v3.GetSize() << " " << v3 << endl;
    v2 = v3;
    cout << v2.GetCapacity() << " " << v2.GetSize() << " " << v2 << endl;

    int a[]{ 9,1,5,3,4 };
    Vector<int> v4(a, 5);
    cout << v4.GetCapacity() << " " << v4.GetSize() << " " << v4 << endl;

    v4.sort();
    cout << "排序后：" << endl;
    cout << v4 << endl;

    char b[]{ '9','1','5','3','4' };
    Vector<char> v5(b, 5);
    cout << v5.GetCapacity() << " " << v5.GetSize() << " " << v5 << endl;
}

int main()
{
    //Test1();
    Test2();
    return 0;
}