2 problems

Let ${\mit\Gamma}$ be an undirected graph, and consider the proper subclass of orientable modular graphs mentioned in Karzanov's tractability conjecture, which includes frames and…

Let ${\mit\Gamma}$ be an undirected graph, and let ${\bf 0\text{-}Ext}[{\mit\Gamma}]$ denote the corresponding minimum $0$-extension problem. An orientable modular graph is an orie…