#include<iostream>
#include<map>
#include<list>
#include<string>
#include<vector>
using namespace std;
void main() {
vector<int> v;
v.reserve(3);
v.push_back(10);
v.push_back(20);
v.push_back(30);
vector<int>::iterator iter = v.begin();
while (iter != v.end())
{
cout << *iter << endl;
iter++;
}
}