P versus NP

P versus NP is considered as one of the most important open problems in computer science. This consists in knowing the answer of the following question: Is P equal to NP? To attack the P = NP question the concept of NP-completeness is very useful. If any single NP-complete problem is in P, then P = NP. We prove there is a problem in NP-complete and P. Therefore, we demonstrate P = NP.