+save(item: Item)
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:，这一点在旺商聊官方下载中也有详细论述
"code": "invalid_amount",。关于这个话题，Line官方版本下载提供了深入分析
"It just really puts into perspective our place among the solar system."
"The big thing will be seeing friends and family and the people who they were expecting to spend Christmas with," said Helen Sharman, Britain's first astronaut.