title: Which STL Container?
body: <p>I need a container (not necessarily a STL container) which let me do the following easily:</p>
  
  <ul>
  <li>Insertion and removal of elements at any position</li>
  <li>Accessing elements by their index</li>
  <li>Iterate over the elements in any order</li>
  </ul>
  
  <p>I used <strong>std::list</strong>, but it won't let me insert at any position (it does, but for that I'll have to iterate over all elements and then insert at the position I want, which is slow, as the list may be huge). So can you recommend any efficient solution?</p>