  A new class UF of problems is introduced, strictly included in the class NP, which arises in the analysis of the time verifying the intermediate results of computations. The implications of the introduction of this class are considered. First of all, we prove that $P\not= NP$ and establish that it needs to consider the problem "P vs UF" instead the problem "P vs NP". Also, we determine the set-theoretical of properties of a one-way functions that used in cryptology. 
On the structure of the class NP