vector初始化

    vector<int> v2;v2.push_back(333);v2.push_back(444);v2.push_back(555);//初始化的两种方式vector<int> v3 = v2;while (v3.size() > 0) {cout << "v3尾部元素" << v3.back() << endl;v3.pop_back();}vector<int> v4(v2.begin(), v2.end());while (v4.size() > 0) {cout << "v4尾部元素" << v4.back() << endl;v4.pop_back();}

vector大小

    //初始化了19个元素，那么再添加就是第20个vector<int> v(19);v.push_back(200);v.push_back(300);cout << "v.size="<<v.size()<< endl;

数组方式操作vector

    cout << "数组。。。。。。。。。"<< endl;vector<int> v(10);for (int i = 0; i < 10; i++) {v[i] = i + 100;}for (int i = 0; i < 10; i++) {cout << v.at(i)<< endl;}

迭代器方式操作vector

    vector<int> v(10);for (int i = 0; i < 10; i++) {v[i] = i + 1000;}for (vector<int>::iterator it = v.begin(); it != v.end(); it++) {cout << *it << " ";}

反向迭代器操作vector

    vector<int> v(10);for (int i = 0; i < 10; i++) {v[i] = i + 1;}for (vector<int>::iterator it = v.begin(); it != v.end(); it++){cout << *it << endl;}//逆向迭代器for (vector<int>::reverse_iterator it = v.rbegin(); it != v.rend(); it++) {cout << *it<< endl;}

vector测试

    vector<int> v1;cout << "length:"<<v1.size()<< endl;v1.push_back(1);v1.push_back(11);v1.push_back(111);cout << "length:" << v1.size() << endl;cout << "头部元素"<<v1.front()<< endl;while (v1.size() > 0) {cout << "尾部元素" << v1.back() << endl;v1.pop_back();}//修改头部元素值//front()返回的是一个引用，可以当左值v1.push_back(000);v1.front() = 222;cout << "修改后的头部元素" << v1.front() << endl;

删除元素

    vector<int> v(10);for (int i = 0; i < 10; i++) {v[i] = i + 100;}for (int i = 0; i < 10; i++) {cout << v.at(i) << endl;}for (vector<int>::iterator it = v.begin(); it !=v.end();) {if (*it == 105) {//删除迭代器所指向元素的时候，erase删除函数会让it自动向后移动一位//所以这总条件下，for循环中的it++就不需要了，另外erase之后会返回//下一位iterator,所以需要通过it接收一次it = v.erase(it);}else {it++;}}//v.erase(v.begin());/*v.erase(v.begin(), v.begin() + 2);*/for (int i = 0; i < 9; i++) {cout << v.at(i) << endl;}

插入元素

    vector<int> v(10);for (int i = 0; i < 10; i++) {v[i] = i + 100;}for (int i = 0; i < 10; i++) {cout << v.at(i) << endl;}v.insert(v.begin(), 99);v.insert(v.end(), 200);for (int i = 0; i < 12; i++) {cout << v.at(i) << endl;}