公车好紧好爽再搔一点浪一点

The core idea is: when the state of the object changes, it changes its behavior at the same time, which is very understandable! Take QQ for example. There are several states, online, invisible, busy, etc. Each state corresponds to different operations, and your friends can also see your state. Therefore, the state mode is two points: 1. You can obtain different behaviors by changing the state. 2. Your friends can see your changes at the same time. Look at the picture:Around these problems, Rui Yi interviewed the founders of some children's thinking ability training institutions, parents who have invested capital in this field and have let their children receive thinking ability training.第二季的成功系列更加有趣，充满了复杂的犯罪！一个新的谜团出现了，贯穿整个赛季。此外，一个新的女性角色加入了这个团队。她是谁，她如何改变主角的生活，这是新一季的另一个有趣之处。FX已宣布续订旗下喜剧《更美好的事》第二季。Apostles: Kahn, Herd, Prey, Casillas, Shilok, Dirigi, Antoine, Rotes, Luke, BacarThis mode applies to scenarios: If we want to add new functions to an existing class, we have to consider several things: 1. Will the new functions have compatibility problems with the existing functions? 2. Will it need to be added later? 3. What if the class does not allow code modification? Facing these problems, the best solution is to use visitor mode, which is suitable for systems with relatively stable data structure, decoupling data structure and algorithm,本来不想求票的，但是今天是周一，来点推荐票、月票、打赏什么的，算是这一周的一个好开始。