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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:
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“致敬未知”完成超亿元Pre-A轮融资
// Signal how many bytes we wrote。服务器推荐是该领域的重要参考
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