向量内存分配策略

i wrote a little piece of code to determine, how memory allocating in a vector is done.

#include <iostream>
#include <vector>
using namespace std;
int main ()
{
  vector<unsigned int> myvector;
  unsigned int capacity = myvector.capacity();

  for(unsigned int i = 0; i <  100000; ++i) {
    myvector.push_back(i);
    if(capacity != myvector.capacity())
    {
      capacity = myvector.capacity();
      cout << myvector.capacity() << endl;
    }
  }
  return 0;
}

我在 Ubuntu 上使用 Visual Studio 2008 和 g++ 4.5.2 编译并得到了以下结果:

capacity = capacity * 1.5;

capacity = capacity * 2;