the sprayer gun have the own sprayer pump or not ? this sprayer gun is only sprayer gun, not have the own sprayer pump, it need to link the sprayer pump to supplier water to work, no any request for ...

背包问题的书，我在Google中搜了很久，有在线阅读的，但是是受限制的，只能阅读某些页码，内容不全。 哪位大侠有，就麻烦 ...