Karp reductions

E519560

Karp reductions are polynomial-time many-one reductions used in computational complexity theory to show that one decision problem is at least as hard as another, central to defining NP-completeness.

All labels observed (2)

Label Occurrences
Karp reductions canonical 1
Levin reduction 1

How this entity was disambiguated

Statements (50)

Predicate Object
instanceOf concept in computational complexity theory ⓘ
polynomial-time many-one reduction ⓘ
reduction between decision problems ⓘ
alsoKnownAs P-time many-one reduction ⓘ
polynomial-time many-one reduction ⓘ
assumptionOnEncoding instances are encoded as finite strings over a fixed alphabet ⓘ
canonicalExampleFrom SAT ⓘ
canonicalExampleTo CLIQUE ⓘ
HAMILTONIAN CYCLE ⓘ
VERTEX COVER ⓘ
category many-one reduction ⓘ
closureProperty transitive ⓘ
codomain decision problem ⓘ
complexityClassContext NP ⓘ
NP-complete ⓘ
P ⓘ
computabilityRequirement reduction function must be computable in polynomial time ⓘ
contrastWith Cook reduction ⓘ
Turing reduction ⓘ
linked to: Turing reducibility
domain decision problem ⓘ
ensuresProperty if B is in P and A ≤_m^P B then A is in P ⓘ
field computational complexity theory ⓘ
formalDefinition a function f from instances of problem A to instances of problem B such that x is in A if and only if f(x) is in B and f is computable in polynomial time ⓘ
impliesHardness if A Karp-reduces to B and A is NP-hard then B is NP-hard ⓘ
importance standard notion of reduction for NP-completeness proofs ⓘ
influencedBy earlier notions of reducibility in recursion theory ⓘ
introducedBy Richard M. Karp ⓘ
linked to: Richard Karp
introducedInWork "Reducibility Among Combinatorial Problems" ⓘ
introducedInYear 1972 ⓘ
logicalForm single call transformation from one instance to another ⓘ
mappingType many-one reduction ⓘ
namedAfter Richard M. Karp ⓘ
linked to: Richard Karp
NPCompleteDefinitionRole a problem is NP-complete if it is in NP and every problem in NP Karp-reduces to it ⓘ
preservesMembership x ∈ A iff f(x) ∈ B ⓘ
problemType decision problems with yes/no answers ⓘ
relatedConcept Cook–Levin theorem ⓘ
complete problems for NP ⓘ
polynomial-time reduction ⓘ
relationToNPCompleteness used to define NP-complete problems ⓘ
requires polynomially bounded output size ⓘ
strongerThan polynomial-time Turing reduction in terms of restriction ⓘ
symbolicNotation ≤_m^P ⓘ
timeComplexityConstraint polynomial time ⓘ
transitivityDescription if A ≤_m^P B and B ≤_m^P C then A ≤_m^P C ⓘ
usedFor comparing hardness of decision problems ⓘ
proving NP-completeness ⓘ
showing one problem is at least as hard as another ⓘ
usedIn classification of NP-complete problems ⓘ
reductions between SAT and other problems ⓘ
usedToShow NP-hardness of optimization problems via decision versions ⓘ

How these facts were elicited

Referenced by (2)

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

Richard Karp → notableConcept → Karp reductions ⓘ
Leonid Levin → notableFor → Levin reduction ⓘ
linked to: Karp reductions