A $3-$conjunctive normal form $(3$CNF$)$ formula is a conjunctive normal form $($CNF$)$ formula in which each

OR$-$term is an OR of at most $3$ literals $($variables or negations of variables$).$ Although it may be hard to tell

if a propositional formula F is satisfiable, it is always easy to construct a formula C$.$F $/$ that i