[Boost-users] Container/Algorithm question

Hi, I have some confusion regarding which type of container/algorithm to use to optimize the lookup (not necessarily the insertion) of unique pairs where the definition of unique is: Either member of the pair can occur an infinite/unbounded number of times provided the other member of the pair never occurs more than once: (3,4), (3,5), (3,6), (6,6), (5,6), (4,6)... etc. So what am I looking at? Some container that allows multiple keys of the same value provided the value is always unique. And also multiple values of the same value provided the key is always unique. Is there such a thing, or something better suited? Thanks, Elisha Berns e.berns@computer.org tel. (310) 556 - 8332 fax (310) 556 - 2839