算法概论——课后习题8.3
问题
STINGY SAT is the following problem: given a set of clauses (each a disjunction of literals) and
an integer k, and a satisfying assignment in which at most k variables are true, if such an
assignment exists. Prove that STINGY SAT is NP-complete.
证明
证明STINGY SAT是一个NPC问题,只需要2步:
- STINGY SAT是一个NP问题:STINGY SAT问题的解可以在多项式时间内验证。
- 可以将SAT问题归约到STINGY SAT问题:将k设成SAT问题中变量的个数。
综上,STINGY SAT是一个NPC问题。