P not equal to NP

This article finds the answer to the question: for any problem from which a non-deterministic algorithm can be derived which verifies whether an answer is correct or not in polynomial time (complexity class NP), is it possible to create an algorithm that finds the right answer to the problem in polynomial time (complexity class P)? For this purpose, this article shows a decision problem and analyzes it to demonstrate that this problem does not belong to the complexity class P, but it belongs to the class NP; doing so it will be proved that it exists at least one problem that belongs to class NP but not to class P, which means that this article will prove that not all NP problems are P.