In this paper, we investigate the existence of parameterized algorithms running in subexponential time for two fundamental cycle-hitting problems: Feedback Vertex Set (FVS) and Triangle Hitting (TH). We focus on the class of pseudo-disk graphs, which forms a common generalization of several graph classes where such results exist, like disk graphs and square graphs. In these graphs, we show that TH can be solved in time $2^{O(k^{3/4}\log k)}n^{O(1)}$, and given a geometric representation FVS can be solved in time $2^{O(k^{6/7}\log k)}n^{O(1)}$.
翻译:本文研究了两个基本的环路命中问题——反馈顶点集(FVS)与三角形命中(TH)——是否存在亚指数时间的参数化算法。我们聚焦于伪圆盘图类,该类是对多个已知存在此类结果的图类(如圆盘图与正方形图)的共同推广。在此类图中,我们证明TH问题可在$2^{O(k^{3/4}\log k)}n^{O(1)}$时间内求解,而在给定几何表示的情况下,FVS问题可在$2^{O(k^{6/7}\log k)}n^{O(1)}$时间内求解。