Suppose X is NP-Complete, X is solvable in polynomial time, if and only if "P = NP". **How to establish NP-completeness of problem "Y". **: step1: Show that "Y" is in NP. step2: Choose an NP-complete problem X. step3: Prove that "X" can be reduced to "Y"....
=NP这个问题n仍然没有被证明出来。 NP complete问题是对于一个问题,我们不能够在多项式时间内进行求解,但是能够在多项式时间内确定一个解是不是该问题的解。
A decision problem P1 is polynomially reducible to a decision problem P2 (if given any instance of P1 we can convert it to an instance of P2 in polynomial time), so that P1 is true if and only if P2 is true. We write P1=<P2, which means that P1 is at least as hard as P2. N...
...由于NP-hard和NP-complete同属的所有NP类都可以归约为它们的这种问题, 而NP-hard还不能确定是不是NP问题, 所以它应该更难一些, 所以有P≤NP≤NPcomplete≤NPhard...我们一般认为P问题是易解问题,而NP-complete以上的就是难解问题。 ? P-NP问题的关系 小可:嗯,我懂了。 Mr....
如果问题A既是NP-Hard又是NP,那么它就是NP-Complete。 从定义我们很容易看出,NP-Hard问题类包含了NP- Complete类(NP完全的定义更严格) 但进一步的我们会问,是否有属于NP-Hard但不属于NP-Complete的问题呢?答案是肯定的。 例如停机问题,也即给出一个程序和输入,判定它的运行是否会终止。
结论是,NP中有最难的一类问题。这类问题就是NP-Complete问题。 最难,就意味着所有NP类的问题都能归约到这个问题上。该问题本身也是NP问题。 所以,NP-Complete问题的形式化定义是: L是NP-Complete问题,当其满足如下两个条件: L∈ NP 任意L1 ∈ NP, L1 可以归约到 L ...
proof NP-complete Hi guys I have a question. I am wondering if anyone know how to proof it. Here is the question: The Subset Sum problem is shown to be NP-complete. The input is a sequence of positive numbers w1, ... ,wn, W, where W is the target weight. The problem is to ...
I am trying to understand the difference between NP-Complete and NP-Hard. Below is my understanding An NP-Hard problem is one that is not solvable in polynomial time but can be verified in polynomial time. An NP-Complete problem is one that is in NP and is also NP-Hard. Is the ...
图示NP, P, NP-Complete和NP-Hard问题 P问题是一类可以通过确定性图灵机(以下简称图灵机)在多项式时间(Polynomial time)内解决的问题集合。 NP问题是一类可以通过非确定性图灵机( Non-deterministic Turing Machine)在多项式时间(Polynomial time)内解决的决策问题集合。
简单理解 NP, P, NP-complete和NP-Hard P是一类可以通过确定性图灵机(以下简称 图灵机)在多项式时间(Polynomial time)内解决的问题集合。 NP是一类可以通过非确定性图灵机(Non-deterministic Turing Machine)在多项式时间(Polynomial time)内解决的决策问题集合。