On the inverse mostar index problem for molecular graphs

Mostar indices are recently proposed distance-based graph invariants, that already have been much investigated and found applications. In this paper, we investigate the inverse problem for Mostar indices of unicyclic and bicyclic molecular graphs. We prove that all positive integers other than 1, 2, 3, and 5 can be the Mostar index of some bicyclic molecular graph. In addition, we resolve the inverse edge Mostar index problem for molecular unicyclic and bicyclic graphs, and in doing so, establish the second and third smallest value of the edge Mostar index of unicyclic graphs.