We study online partitioning of posets from a graph theoretical point of view, which is coloring and cocoloring in comparability graphs. For the coloring problem, we analyse the First-Fit algorithm and show a ratio of ; furthermore, we devise an algorithm with a competitivity ratio of . For the cocoloring problem, we point out a tight bound of and we give better bounds in some more restricted cocoloring problems.
Istvan Tomon, Dániel József Korándi