c – 添加新项目时,哪种数据结构会丢弃最旧的项目？

http://www.boost.org/doc/libs/1_46_1/libs/circular_buffer/doc/circular_buffer.html

来自Boost文档：

// Create a circular buffer with a capacity for 3 integers.
  boost::circular_buffer<int> cb(3);

  // Insert some elements into the buffer.
  cb.push_back(1);
  cb.push_back(2);
  cb.push_back(3);

  int a = cb[0];  // a == 1
  int b = cb[1];  // b == 2
  int c = cb[2];  // c == 3

  // The buffer is full Now,pushing subsequent
  // elements will overwrite the front-most elements.

  cb.push_back(4);  // Overwrite 1 with 4.
  cb.push_back(5);  // Overwrite 2 with 5.

  // The buffer Now contains 3,4 and 5.

  a = cb[0];  // a == 3
  b = cb[1];  // b == 4
  c = cb[2];  // c == 5