Before revision:  Here, we are given a colored point set , where the points are covered by (unknown) k clusters, which are monochromatic (i.e., all the points covered by the same cluster, have the same color).
After revision:  Here, we are given a colored point set where the points are covered by (unknown) k clusters, which are monochromatic (i.e., all the points covered by the same cluster, have the same color).