學習筆記-C++ STL iterator與對指針的理解-20170618

vector的itrerator支持random access

#include<iostream>
#include<vector>
using namespace std;
int main()
{
    vector<int>intVector;
    intVector.push_back(10);
    intVector.push_back(20);
    intVector.push_back(30);
    intVector.push_back(40);
    intVector.push_back(50);
    intVector.push_back(60);

    vector<int>::iterator p1 = intVector.begin();
    for (; p1 != intVector.end(); p1++)
    {
        cout << *p1 <<" " <<&p1<<endl;
    }
    //cout <<endl<< "the last" << *p1 << endl; //  vector iterator is not dereferencable 
    cout <<endl<< &p1 <<endl;
    cout  << *(--p1) << "  "<<&p1<<endl;//60

    cout << *(p1 - 3) <<" "<<&p1<< endl;
    cout << p1[-3] << " "<<&p1<<endl;
    cout << *p1 << "  " << &p1<< endl;
    *p1 = 1234;
    cout << *p1 << " " << &p1 << endl;
    for (; p1 != intVector.end(); p1++)
    {
        cout << *p1 << " " << &p1 << endl;
    }
    cout << endl << endl;
    for (p1=intVector.begin(); p1 != intVector.end(); p1++)
    {
        cout << *p1 << " " << &p1 << endl;
    }
    cin.get();
    return 0;
}

輸出：

10 00FEFCF4
20 00FEFCF4
30 00FEFCF4
40 00FEFCF4
50 00FEFCF4
60 00FEFCF4

00FEFCF4
60  00FEFCF4
30 00FEFCF4
30 00FEFCF4
60  00FEFCF4
1234 00FEFCF4
1234 00FEFCF4

10 00FEFCF4
20 00FEFCF4
30 00FEFCF4
40 00FEFCF4
50 00FEFCF4
1234 00FEFCF4

PS：①當iterator指向容器中最后一個元素后面一個位置時（空），無法解引用

         ②iterator相當於指針，對iterator進行++或--時，iterator指向的位置前移或后移，但是iterator本身的地址是不變的，和指針一樣