NP problem, NPC problem and NPC problem

NP problem NPC and NPC problem

P-Class Problems: If a problem can be found in a polynomial time to solve its algorithm, then this problem belongs to the P problem.

NP problem: Refers to the problem of validating a solution in polynomial time. Another definition of NP problem is that you can guess the problem of a solution in polynomial time.

Obviously, all P-class problems are NP-related. The point is that people want to know if all NP problems are P-type.

NPC question: At the same time meeting the following two conditions is the NPC problem. First, it has to be a NP problem, and then all NP problems can be reduced to it.

Np-hard problem: It satisfies the NPC question definition of the second article but not necessarily satisfies the first (that is, the np-hard problem is wider than the NPC problem)

Reference: 1, what are P problems, NP problems, and NPC questions

2. Turing and NP-hard problems

NP problem, NPC problem and NPC problem