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arXiv · 2402.16923

On solving basic equations over the semiring of functional digraphs

Alberto Dennunzio·Enrico Formenti·Luciano Margara·Sara Riva
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Abstract

Endowing the set of functional graphs (FGs) with the sum (disjoint union of graphs) and product (standard direct product on graphs) operations induces on FGs a structure of a commutative semiring R. The operations on R can be naturally extended to the set of univariate polynomials R[X] over R. This paper provides a polynomial time algorithm for deciding if equations of the type AX=B have solutions when A is just a single cycle and B a set of cycles of identical size. We also prove a similar complexity result for some variants of the previous equation.

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Alberto Dennunzio, Enrico Formenti, Luciano Margara, Sara Riva. 2024-02-26. On solving basic equations over the semiring of functional digraphs. https://doi.org/10.46298/dmtcs.14590

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