The (Perfect) Matching Cut is to decide if a graph has a (perfect) matching that is also an edge cut. The Disconnected Perfect Matching problem is to decide if a graph has a perfect matching that contains a matching cut. Both Matching Cut and Disconnected Perfect Matching are NP-complete for planar graphs of girth 5, whereas Perfect Matching Cut is known to be NP-complete even for graphs of arbitrarily large fixed girth. We prove the last result also for the other two problems, solving a 20-year old problem for Matching Cut. Moreover, we give three new general hardness constructions, which imply that all three problems are NP-complete for H-free graphs whenever H contains a connected component with two vertices of degree at least 3. Afterwards, we update the state-of-the-art summaries for H-free graphs and compare them with each other. Finally, by combining our new hardness construction for Perfect Matching Cut with two existing results, we obtain a complete complexity classification of Perfect Matching Cut for H-subgraph-free graphs where H is any finite set of graphs.
翻译:匹配剪切( Perfect) 是要决定一个图形是否有匹配( perfect) 的匹配( perfect), 同时也是边缘剪切 。 断开的完美匹配问题是要决定一个图形是否有匹配剪切的完美匹配。 匹配剪切( perfect) 和断开的完美匹配( perfect Contracting) 都对5 的平面图完成了 NP 。 而完美匹配剪切除( perfect) 已知甚至任意大固定壁的图形也是 NP 。 我们证明其他两个问题的最后结果也是最后的结果, 解决了 匹配剪切的20 年问题 。 此外, 我们给出了三个新的一般硬度构造, 这意味着只要 H 包含两个顶点的连接组件, 至少有 3 。 之后, 我们更新了无 H 图表的状态艺术摘要, 并相互比较 。 最后, 通过将我们新的 匹配剪切的硬度构造与两个现有结果结合起来, 我们获得了一个完全复杂的 H imforphrifrifor- put- put- put 图形的完全匹配剪切 分类 。