C++学习之vector容器笔记

#include <iostream>

#include <vector>

#include <string>

using namespace std;

class Student

{

public :

    Student(){cout << "Student() is dead..." <<endl;}

    ~Student(){cout << "~Student() is here..." << endl;}

    Sutdent(const Student &stu)

    {

        m_strName = stu.m_strName;

        m_fScore = stu.m_fScore;

        cout << "Student(const Student &) is here... " << endl;

    }

    Student(string name,float score)

    {

        m_strName = name;

        m_fScore = score;

        cout << "Student(aguments)..." <<endl;

    }

/**

    friend void print(const vector<Student>&vec)

    {

        vector<Student>::const_iterator iter;

        iter = vec.begin();

        for(;iter!=vec.end();iter++)

        {

            cout << *iter->stu.m_stuName << endl;

        }

    }

**/

private:

    string m_strName;

    float m_fScore;

};

//typedef vector<Student> VECSTU;

typedef vector<Student*> VECSTU;

/**自定义释放函数**/

void freeVec(VECSTU &vecStu)

{

    VECSTU::iterator iter = vecStu.begin();

    for (; iter != vecStu.end(); iter++)

    {

        delete (*iter);

    }

}

void print(const vector<int> &vec)

{

    vector<int>::const_iterator iter = vec.begin();//迭代器

    for(;iter !=vec.end();iter++)

    {

        cout << *iter <<' ';

    }

    cout << endl;

}

typedef vector<int> VECINT;

int main(void)

{

#if 0

    vector<int> vec_int;

    for(int i =0;i<10;i++)

    {

         //push_back:将数据放到容器里的最后

        vec_int.push_back(i+10);

        //capacity:获得容器实际存储容量的大小

        cout << vec_int.capacity() << endl;

    }

    //size:获得容器元素的个数

    for(int i=0;i<vec_int.size();i++)

    {

        //当容器中存在存储空间才可以使用下标访问数据

        //注意不要越界，没有做越界检查

        //cout<<vec_int[i]<<' ' << endl;

        cout << vec_int.at(i) << ' ';

    }

    cout << endl;

    /**

    verctor<int>是声明向量容器；

    例如 verctor<int> v,就是创建了一个名字叫v的向量容器。

    vector<int>::iterator是定义向量迭代器

    例如，vector<int>::iterator it 就可以

    for(it=v.begin();it!=v.end();it++)

    cout<<*it<<endl;

    就把里面的内容都输出了

    **/

    vector<int>::iterator iter;

    iter = vec_int.begin();

    for(;iter!=vec_int.end();iter++)

    {

        cout << *iter << ' ';

    }

    cout << endl;

#endif

#if 0

    int iaData[6] = {11,32,15,17,26,19};

    //vector<int> vec(iaData,iaData + 6);//从数组的第一个值到数组第六个值

    vector<int> vec(10,999);//插入10个数，每个都是999

    for(int i = 0;i < vec.size();i++)

    {

        cout << vec[i] << ' ';

    }

   cout << endl;

   cout << vec.capacity() << endl;

   for(int i =0;i<vec.size();i++)

   {

    cout << vec[i] << ' ';

   }

   cout << endl;

   cout << "11111111111111111111111111111111111111" <<endl;

   vec.assign(2,888);

   cout << vec.capacity() << endl;

   for(int i = 0;i<vec.size();i++)

   {

    cout << vec[i] << ' ';

    }

   cout << endl;

   cout << "22222222222222222222222222222222222222" << endl;

   cout << vec.max_size() << endl;

   if(vec.empty())

   {

    cout << "vector is empty" << endl;

   }else

   {

   cout << "vec id not empty"<<endl;

   }

   vec.reserve(1024);

   cout << vec.capacity() <<endl;

   for(int i = 0;i<vec.size();i++)

   {

    cout << vec[i] <<' ';

   }

   cout << endl;

   vec.push_back(111);

   printf("3333333333333333333333333333333333\n");

   cout << vec.back() << ' ' << vec.front() <<endl;

#endif

#if 0

   //vector<int> vec_int;

    VECINT vec_int;

    for(int i =0;i < 10;i++)

    {

        vec_int.push_back(i+10);

    }

    vector<int>::iterator iter;

    iter = vec_int.begin();

    cout << *iter << endl;

    for(;iter!=vec_int.end();iter++)

    {

       cout << *iter << ' ';

    }

    cout << endl;

    cout << "first function test like above" <<endl;

    iter = vec_int.begin();

    for(;iter!=vec_int.end();iter++)

    {

        *iter +=10;

    }

    iter = vec_int.begin();

    for(;iter !=vec_int.end();iter++)

    {

        cout << *iter << ' ';

    }

    cout << endl;

    cout << "second function test like above" << endl;

    vector<int>::const_iterator const_iter;

    const_iter = vec_int.begin();

    cout << *const_iter << endl;

    //*const_iter = 666;/error

    for(;const_iter != vec_int.end();const_iter++)

    {

        cout << *const_iter << ' ';

    }

    cout << endl;

    cout << "third function test this above" << endl;

    iter = vec_int.begin();

    vec_int.insert(iter,698);

    iter = vec_int.begin();

    cout << *iter << endl;

    cout << "fouth function test this above" <<endl;

    iter++;

    iter++;

    vec_int.insert(iter,3,899);//插入三个数

    iter = vec_int.begin();

    for(;iter != vec_int.end();iter++)

    {

        cout << *iter << ' ';

    }

    cout << endl;

    cout << "ffith function test this above" <<endl;

    int iaData[] = {1,2,3,4,5,6,7,8,9};

    iter = vec_int.begin();

    iter++;

    vec_int.insert(iter,iaData,iaData + 8);//插入数组

    iter = vec_int.begin();

    for(;iter != vec_int.end();iter++)

    {

        cout << *iter << ' ';

    }

    cout << endl;

    cout << "sixth function test is above" <<endl;

    cout << vec_int.capacity() <<endl;

    iter = vec_int.begin();

   // iter = vec_int.begin();

   /** for(;iter != vec_int.end();iter++)

    {

        cout << *iter << ' ';

    }

    cout << endl;

**/

    //iter = vec_int.end();

    vec_int.insert(iter,2,88);

    for(;iter !=vec_int.end();iter++)

    {

        if(0 != *iter %2)

        {

            //增删数据后，所有的迭代器均失效，需要重新赋值

            //erase:返回一个迭代器，

            //该迭代器指向下一个元素或者end()

             //只是将元素删除，并不会对存储空间产生影响

            //erase()函数的功能是用来删除容器中的元素。

            /**

函数原型:

iterator erase(iterator where);

iterator erase(iterator first,iterator last);

basic_string& erase(size_type p0=0,size_type n=np);

删除某个容器里的某个元素：c.erase(T);

链表容器以list为例，执行container.erase(it)。

list<int>::iterator it;

for (it = lt.begin(); it != lt.end(); ) {

if (*it % 2 == 0)

lt.erase(it++);

else

++it;

}

            **/

             iter = vec_int.erase(iter);

        }else

        {

            iter++;

        }

    }

    cout << vec_int.capacity() <<endl;

    iter = vec_int.begin();

    for(;iter != vec_int.end();iter++)

    {

        cout << *iter << ' ';

    }

    cout << endl;

    print(vec_int);

    cout << "this test is below"<< endl;

        VECINT::iterator iter1 = vec_int.begin();

        VECINT::iterator iter2 = vec_int.begin();

        iter2++;

        iter2++;

        vec_int.erase(iter1, iter2); //[iter1, iter2);

        print(vec_int);

#endif

#if 0

    VECSTU stuVec;

    Student stu("zhangsan",99);

    for(int i=0;i<5;i++)

    {

        stuVec.push_back(stu);

    }

#endif

    VECSTU stuVec;

        Student *pStu = NULL;

        cout << "----------------------------" << endl;

        for (int i = 0; i < 5; i++)

        {

            pStu = new Student("zhangsan", i + 100);

            stuVec.push_back(pStu);

        }

        freeVec(stuVec);

    // cout << stuVec.at(0).m_strName <<endl;

    cout << "Hello World!" << endl;

    return 0;

}