NP-completeness

E173625

NP-completeness is a central concept in computational complexity theory that classifies decision problems believed to be among the hardest in NP, such that a polynomial-time solution to any one of them would yield polynomial-time solutions to all problems in NP.

All labels observed (4)

Label Occurrences
NP-completeness canonical 4
Cook–Levin theorem 1
Karp’s 21 NP-complete problems 1

How this entity was disambiguated

Statements (50)

Predicate Object
instanceOf complexity class property
computational complexity theory concept
assumesConjecture P ≠ NP (widely believed)
centralReference Garey and Johnson: Computers and Intractability
Papadimitriou: Computational Complexity
Introduction to the Theory of Computation
surface form: Sipser: Introduction to the Theory of Computation
characterizes hardest problems in NP
closureProperty closed under polynomial-time many-one reductions
concerns worst-case time complexity
consequenceOfIntractability if all NP-complete problems are intractable then P ≠ NP
consequenceOfPTimeSolution P = NP if any NP-complete problem has a polynomial-time algorithm
definedOver decision problems
dependsOn definition of NP
nondeterministic Turing machine model
polynomial-time computability
field computational complexity theory
theoretical computer science
firstNPCompleteProblem Cook–Levin theorem
surface form: Boolean satisfiability problem
firstNPCompleteProof Cook–Levin theorem
formalDefinition A decision problem L is NP-complete if L is in NP and every problem in NP is polynomial-time reducible to L
hasCanonicalProblem 3-SAT
Clique problem
Hamiltonian cycle problem
SAT
Subset sum problem
Traveling salesman decision problem
Vertex cover problem
hasVariant #P-completeness
PSPACE-completeness
co-NP-completeness
parameterized NP-completeness (W[1]-hardness etc.)
implies NP-hardness
membership in NP
problem is at least as hard as every problem in NP
introducedBy Leonid Levin
Stephen Cook
introductionYear 1971
oftenAnalyzedWith reduction chains between problems
relatedTo NP
NP-hardness
P versus NP problem
requires NP-hardness
belonging to NP
studiedIn complexity theory textbooks
typicalAssumption NP-complete problems do not admit polynomial-time algorithms
typicalProofMethod polynomial-time reduction from known NP-complete problem
usedFor classifying computational intractability
showing hardness of approximation in some contexts
usesReductionType Karp reduction
polynomial-time many-one reduction

How these facts were elicited

Referenced by (7)

Full triples — surface form annotated when it differs from this entity's canonical label.

Introduction to Algorithms coversTopic NP-completeness
Stephen Cook knownFor NP-completeness
Stephen Cook knownFor NP-completeness
this entity surface form: Cook–Levin theorem
Richard Karp knownFor NP-completeness
this entity surface form: theory of NP-completeness
Richard Karp knownFor NP-completeness
this entity surface form: Karp’s 21 NP-complete problems
P versus NP problem relatedConcept NP-completeness
"Introduction to Automata Theory, Languages, and Computation" topic NP-completeness
subject surface form: Introduction to Automata Theory, Languages, and Computation