vector的一点使用

这里主要是尝试使用了vector的一些基本方法以及将vector作为vector的模版来使用的两种情况，程序也很简单。如下：
（因为使用哪个“插入代码”功能实在等不下去了，就直接粘贴了）
#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

int main(int argc, char *argv[])
{
vector<int> v;
for (int i = 0; i<5 ;i++ )
{
v.push_back(i);
}
// copy the vector to the screen, from first to last.
copy(v.begin(),v.end(),ostream_iterator<int>(cout," "));
cout<<endl;
// get the top element of th vector
int i=v.back();
cout<<i<<endl;
// // get the bottom element of th vector
i=v.front();
cout<<i<<endl;
// copy the vector to the screen from last ro first
copy(v.rbegin(),v.rend(),ostream_iterator<int>(cout," "));
cout<<endl;
// get the element at specific place
cout<<v.at(2)<<endl;

return 0;
}
该程序运行结果如下：
0 1 2 3 4
4
0
4 3 2 1 0
2

另外一个使用vector作为vector的模版的程序：
#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

int main(int argc, char *argv[])
{

vector<vector<int>> vv;

vector<int> vi;
vi.push_back(4);
vi.push_back(6);
vv.push_back(vi);

vector<int> vi1;
vi1.push_back(1);
vi1.push_back(2);
vv.push_back(vi1);

int c = 0;
// get the vector's capacity. If using size(), it should be as follows:
// int s = vv.size();
// while (c<s) {...}
// note: "while(c<vv.size) {...}" won't get the last element. After pop_back(), the size() decreases.
while (c<vv.capacity())
{
/* first, get the top element via back(), copy its elements to screen;
* then pop up it to make the top the next element.
*/
vector<int> v = vv.back();
copy(v.begin(),v.end(),ostream_iterator<int>(cout," "));
cout<<endl;
vv.pop_back();
c++;
}

return 0;
}
该程序结果如下：
1 2
4 6

我相信，只要努力学习，总会有收获的。