Intermediate
Theory of Computation
Q59 / 100
What is the polynomial hierarchy?
Correct! Well done.
Incorrect.
The correct answer is B) A hierarchy of complexity classes Σₖᴾ, Πₖᴾ generalizing NP and co-NP with alternating quantifiers
B
Correct Answer
A hierarchy of complexity classes Σₖᴾ, Πₖᴾ generalizing NP and co-NP with alternating quantifiers
Explanation
PH = ∪ Σₖᴾ where Σ₀ᴾ = P, Σ₁ᴾ = NP, Π₁ᴾ = co-NP, Σ₂ᴾ = NP^NP, etc. If any level collapses (Σₖ = Πₖ), the entire hierarchy collapses.
Progress
59/100