Table of Contents
- 1 What is the difference between NP-hard and NP-complete?
- 2 What is NP-hard but not NP-complete?
- 3 What is NP-hard and NP-complete in DAA?
- 4 What does NP-complete mean?
- 5 What is the difference between P and NP problems?
- 6 What makes NP-hard difficult?
- 7 Is chess NP complete or NP hard?
- 8 What is an instance of NP complete problem?
What is the difference between NP-hard and NP-complete?
The NP problems set of problems whose solutions are hard to find but easy to verify and are solved by Non-Deterministic Machine in polynomial time. Attention reader!…Difference between NP-Hard and NP-Complete:
| NP-hard | NP-Complete |
|---|---|
| To solve this problem, it do not have to be in NP . | To solve this problem, it must be both NP and NP-hard problems. |
What is NP-hard but not NP-complete?
The set of NP-hard problems is a superset of the set of NP-complete problems. There are complexity classes more “difficult” than NP, for example PSPACE, EXPTIME or EXPSPACE, and all these contain NP-hard but not NP-complete problems.
What are P NP-hard and NP-complete problems?
P is a set of problems that can be solved by a deterministic Turing machine in Polynomial time. NP is set of decision problems that can be solved by a Non-deterministic Turing Machine in Polynomial time. NP-complete problems are the hardest problems in the NP set.
What is harder than NP-complete?
The set of NP-hard problems is a superset of the set of NP-complete problems. There are complexity classes more “difficult” than NP, for example PSPACE, EXPTIME or EXPSPACE, and all these contain NP-hard but not NP-complete problems. NP-complete must be NP and NP-hard.
What is NP-hard and NP-complete in DAA?
A problem is NP-hard if all problems in NP are polynomial time reducible to it, even though it may not be in NP itself. If a polynomial time algorithm exists for any of these problems, all problems in NP would be polynomial time solvable. These problems are called NP-complete.
What does NP-complete mean?
(definition) Definition: The complexity class of decision problems for which answers can be checked for correctness, given a certificate, by an algorithm whose run time is polynomial in the size of the input (that is, it is NP) and no other NP problem is more than a polynomial factor harder.
Is NP-hard harder than NP?
NP complete problem is both NP and NP-hard by definition. So NP-complete problems are not harder than NP problems – but they are as hard as least as any non-trivial problem in NP, and might be harder than P and NP-intermediate in case P≠NP.
Is TSP NP-complete?
Traveling Salesman Optimization(TSP-OPT) is a NP-hard problem and Traveling Salesman Search(TSP) is NP-complete. However, TSP-OPT can be reduced to TSP since if TSP can be solved in polynomial time, then so can TSP-OPT(1).
What is the difference between P and NP problems?
Roughly speaking, P is a set of relatively easy problems, and NP is a set that includes what seem to be very, very hard problems, so P = NP would imply that the apparently hard problems actually have relatively easy solutions.
What makes NP-hard difficult?
A problem is NP-hard if an algorithm for solving it can be translated into one for solving any NP-problem (nondeterministic polynomial time) problem. NP-hard therefore means “at least as hard as any NP-problem,” although it might, in fact, be harder.
Is NP-hard polynomial time?
In computational complexity theory, NP-hardness (non-deterministic polynomial-time hardness) is the defining property of a class of problems that are informally “at least as hard as the hardest problems in NP”. A simple example of an NP-hard problem is the subset sum problem.
What is NP-hard in DAA?
Is chess NP complete or NP hard?
NP-complete is the hard parts of NP. Or, NP is superset of P and NP-complete. EXP is exponential. Not only is it ridiculously hard to solve, but also equally hard to check if your answer is correct. Like the best move in chess. NP-hard can be thought of as a super set of P, NP, and EXP.
What is an instance of NP complete problem?
The classic example of “NP-Complete” problems is the Traveling Salesman Problem. Imagine you need to visit 5 cities on your sales tour. You know all the distances.
P versus NP. Every decision problem that is solvable by a deterministic polynomial time algorithm is also solvable by a polynomial time non-deterministic algorithm. All problems in P can be solved with polynomial time algorithms, whereas all problems in NP – P are intractable. It is not known whether P = NP. However, many problems are known in NP with the property that if they belong to P, then it can be proved that P = NP.
What is NP algorithm?
An NP algorithm is an algorithm that has 2 stages: The first stage is a guessing stage that uses choose() to find a solution to the problem. The second stage checks the correctness of the solution produced by the first stage. The time of this stage is polynomial in the input size n. Template for an NP algorithm: