In this book the authors introduce the new notions of subset polynomial semirings and subset matrix semirings. Solving subset polynomial equations is an interesting exercise. Open problems about the solution set of subset polynomials are proposed.

In this book the new notion of interval semirings are introduced. New structures like interval groups are used to construct interval group semirings. Further non-associative interval semirings are constructed using loops and groupoids. We have given 284 examples, 118 problems are proposed ¿ some of them at the research level.The main keywords are interval semirings, interval groups, interval matrix semirings, interval groupoid semirings, neutrosophic interval semirings, and loop interval semirings.

This book provides an introduction to the algebraic theory of semirings and, in this context, to basic algebraic concepts as e.g. semigroups, lattices and rings. It includes an algebraic theory of infinite sums as well as a detailed treatment of several applications in theoretical computer science. Complete proofs, various examples and exercises (some of them with solutions) make the book suitable for self-study. On the other hand, a more experienced reader who looks for information about the most common concepts and results on semirings will find cross-references throughout the book, a comprehensive bibliography and various hints to it.