On terminal delta-wye reducibility of planar graphs
Isidoro Gitler, Feliú Sagols · Networks · 2011
We prove terminal Δ-Y reducibility of planar graphs with at most three terminals. The most important consequence of our proof is that this implicitly gives an efficient algorithm with time complexity O(|E(G)|4) for reducibility of planar graphs G with at most three terminals. It also can be used for restricted reducibility problems with more terminals. Our proof uses a very well-known translation from these operations to transformations on the medial graph. © 2010 Wiley Periodicals, Inc. NETWORKS, Vol. 57(2), 174–186 2011