Graham Coulson first joined his town's musical theatre group when he was 14
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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:
办理治安案件的公安机关有前款所列行为的，对负有责任的领导人员和直接责任人员，依法给予处分。