Complexity Classes and Polynomial - time Reductions
نویسندگان
چکیده
The first hard problem we will examine is what is known as Satisfiability or SAT. As input, we are given a set of n boolean variables X = {x1, x2, . . . , xn} (i.e., each variable can be set to either true or false). We are then given a boolean formula over these variables of the following form (noting that this is just a specific example where X = {x1, x2, x3, x4}): (x1 ∨ x2 ∨ x3) ∧ (x2 ∨ x3 ∨ x4) ∧ (x4 ∨ x1 ∨ x2) (1)
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