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NP-Complete problems NP-Complete problems - Ace

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✬✩A Formal Language framework: ReducibilityEvery decision problem has a corresponding language = themaximal set of input strings that produce “yes” answers.Let L A ,L B ⊆ {0,1} ∗ be the languages corresponding to the twodecision <strong>problems</strong> A and B, respectively.Definition: L A is polynomial-time reducible to L B (writtenL A ≤ p L B ) if:• there exists a poly-time computable functionf: {0,1} ∗ → {0,1} ∗• such that for all α ∈ {0,1} ∗α ∈ L A if and only if f(α) ∈ L B .CS404/504✫Design and Analysis of Algorithms: Lecture 26Computer Science6✪

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