(A very useful file verification tool (MD5 SHA1 CRC32), it can also encrypt files, and the compression code is finished, but unfortunately the compilation error is reported, so I have to comment it out. It can also be used as a generation tool for messy passwords, such as using The MD5 value of a simple string, then enter 123, the generated password can be 202cb962, which is okay, it is messy enough, and you only need to remember 123, it also supports AES encryption)