title: I need help choosing the right c++ container
body: <p>key is :(x,y)  , that means 2 integers.</p>
  
  <p>value is: 0 or 1.</p>
  
  <p>And I have frequently operation of iteration of this hash map.</p>
  
  <p>Which data structure is fit? I am using C++ stl or tr1. Don't consider boost.</p>