“When you ask your question, display the fact that you have done these things first; this will help establish that you're not being a lazy sponge and wasting people's time. Better yet, display what you have learned from doing these things. We like answering questions for people who have demonstrated they can learn from the answers.”
Also, knowing what you know and don’t know may make helping you a lot easier, thus increasing the possibility that you’ll get an answer that helps you.
In particular, if you did “Try to find an answer by searching the Web.”, did you find https://en.wikipedia.org/wiki/P_versus_NP_problem? If so, what’s insufficient for you in that?
(I also think http://www.catb.org/~esr/faqs/smart-questions.html#forum applies. IMO, this isn’t the forum to ask these kind of question, but will let the community judge that)