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There is a special form for boolean formulas called "Conjunctive Normal Form" (CNF). A problem in this form consists of clauses connected with and operators, where each clause only contains variables connected with or operators. The variables can appear negated, but only variables can be directly negated, something like !(a && b) is not allowed. An example boolean formula in CNF form is:
（一）刑讯逼供、体罚、打骂、虐待、侮辱他人的；
while(j<31 && !(h=free_table[j])) ++j;