How to Compute the Wiener Index of a Graph*
نویسنده
چکیده
The Wiener index of a graph G is equal to the sum of distances between all pairs of vertices of G, It is known that the Wiener index of a molecular graph correlates with certain physical and chemical properties of a molecule. In the mathematical literature, many good algorithms can be found to eompute the distances m a graph, and these can easily be adapted for the caleulation of the Wiener indcx. An algorithm that calculates the Wiener index of a tree in linear timc is givcn. It improves an algorithm of Canfield, Robinson and Rouvray. The question rcmains: is there an algorithm for general graphs that would eMculate the Wiener index without calculating the distance matrix? Another algorithm that calculates this index for an arbitrary graph is given.
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