#include <iostream>
#include <vector>
using namespace std;
int main ()
{
    vector<int> myvector;
    
    // set some initial content:
    for (int i=1;i<10;i++) myvector.push_back(i);//长度为9
    
    myvector.resize(5);//重新设置长度为5，多余的元素删掉
    myvector.resize(8,100);//重新设置长度为8，填充元素为100
    myvector.resize(12);//默认填充的元素是0
    
    cout << "myvector contains:";
    for (int i=0;i<myvector.size();i++)
        cout << ' ' << myvector[i];
    cout << '\n';
    
    return 0;
}

myvector contains: 1 2 3 4 5 100 100 100 0 0 0 0