Report published in the Proceedings of the National Conference on "Education and Research in the Information Society", Plovdiv, June, 2018In this paper we will expose results connected to the practical realization of Euclidean algorithm in contemporary programming environment (Visual C# 2017) and CAS Wolfram Mathematica. Results of numerical experiments show that algorithm conducting take shorter CPU Time which is one of basic tasks for everyone who is involved in calculations, professional programmer and specialist in applied mathematics. The task of searching greatest common divisor is basic at least for 3 branches of nowadays science: Algebra, Number theory and Discrete Mathematics. Similar tasks are of interest to specialists in paralle...