Before revision:  We also propose a simpler version of our (1 + \epsilon)-approximate algorithm which runs in a factor of \log(c_{high}} / \epsilon) is sublinear. We\epsilon)) from linear time, but is faster in practice.
After revision:  We also propose a simpler version of our (1 + \epsilon)-approximate algorithm which runs in a factor of \log(c_{high}} / (c_{low\epsilon)) from linear time, but is faster in practice.