vector收录在STL里，是一种特殊的数据结构。它的中文名字叫做“动态数组”或者“不定长数组”，有时也被翻译成“容器”

    1. #include <iostream>
    2. #include <vector>
    3. using namespace std;
    4. int main(){
    5.     vector<int> dynArray (3);
    6.     dynArray[0] = 333;
    7.     dynArray[1] = -421;
    8.     dynArray[2] = 888;
    9.     cout << dynArray.size() << endl;
    10.     int newValue = 0;
    11.     cin >> newValue;
    12.     dynArray.push_back(newValue);
    13.     cout << dynArray.size() << endl;
    14.     cout << "last elemente: " << dynArray[dynArray.size() -1 ] << endl;
    15.     return 0; 
    16. }