1.vector

头文件#include <vector>

常见的方法有vector.clear() ; vector.size() ; vector.empty();

遍历输出vector：

#include <iostream>
#include <vector>
using namespace std;
int main(){
    vector<int> a({1,2,3,4});
    for(int i = 0 ; i < a.size() ; i++) cout<<a[i]<<" ";
    cout<<endl;
    
    for(vector<int>::iterator i = a.begin() ; i!=a.end() ; i++) cout<<*i<<" ";
    cout<<endl;
    
    for(auto i = a.begin() ; i!= a.end() ; i++) cout<<*i<<" ";
    cout<<endl;
}