“…The MMM problem is in general NP-hard [4] and therefore the MWMM problem is in general NP-hard as well, whereas the problems of finding a minimum/maximum weighted matching or minimum/maximum weighted perfect matching are all solvable in polynomial time, see, e.g., [5]. In particular, the MMM problem has been shown to be NP-hard in bipartite graphs with maximum degree 3 [4], planar cubic graphs [6], and -regular bipartite graphs for any ≥ 3 [7]. On the positive side, it has been shown that the MMM problem can be solved in polynomial time in some classes of graphs including trees [8], series-parallel graphs [9], and block graphs [10].…”