C++ and OpenMP: the fastest way to iterate over all subsets

I need to iterate over all the k-subsets of n-set (i.e. there will be n choose k subsets). The value of n is approximately 100-200, and the value of k is somewhere around 10. I would also like to do this in a (more or less) parallel manner, as I can on our cluster I can use OpenMP or OpenMPI.

What is the fastest way to do this?

P.S. I don't care much about memory.