Solutions to problems.
包括各种东西。有些可能没有完成，我还没有写完，有些可能会让你的程序崩溃。但是这里有很多东西，什么东西都可以到这里看看，虽然你不一定能找得到。
Including many things. Some are not finished, I am still writing them, some might make your program crash. But there are a lot of things here, you can come here to seek anything but you might not find it.