NP Flashcards
Clique is conceptually the opposite of ____
Independent Set
Set of vertices S of an Independent Set of G is the equivalent to ____.
(with regard to cliques)
Same S of complementary graph for a clique.
“Can Luke Inspect Some Goods?”
Definition of vertex cover
for every (x,y) ∈ E, either x ∈ S or y ∈ S
What is the key claim regarding vertex cover –> I.S. NP reductions?
S is a vertex cover IFF S̄ is an independent set in the the same graph.
“Venture Capital Is So Sexy”
If A –> B, what do we know about B?
That B is at least as hard as A
NP complete is the intersection of…
NP and NP-Hard
All NP-Complete problems are ____, but not all _____ are _____.
- NP-Hard
- NP-Hard
- NP-Complete
Vertex Cover –> Clique Lemma
Vertex cover S IFF complement of S is clique of complement of G.
Relationship between #vertices, #edges in clique
|e| = k(k-1)/2
Clique I/O
INPUT: Graph G and goal g
OUTPUT:
- set of vertices S (clique) with size >= g if possible
- NO otherwise
Vertex Cover I/O
INPUT: graph G and budget b
OUTPUT:
- set of vertices S (vertex cover) <= b if possible
- NO otherwise
Independent Set I/O
INPUT: graph G and goal g
OUTPUT:
- set of vertices S (independent set) >= g if possible
- NO otherwise