A new technique to compute padmakar-ivan index and szeged index of pericondensed benzenoid graphs

Distance properties of molecular graphs form an important topic in chemical graph theory. The Padmakar-Ivan (PI) index of a graph G is the sum over all edges uv of G of the number of edges which are not equidistant from u and v and the Szeged (Sz) index of a graph G is the sum over all edges uv of G of the number of vertices which are not equidistant from u and v. In this paper we evolve an efficient method to calculate the PI index and Szeged index of pericondensed benzenoid graphs (r l), r l = 1 without using distance matrix. We also provide an Or l-linear time algorithm to compute the same.