An error message appears in vim: The ycmd server SHUT DOWN (restart with ':YcmRestartServer'). Unexpected exit code 1.

Reference: https://stackoverflow.com/questions/47667119/ycm-error-the-ycmd-server-shut-down-restart-wit-the-instructions-in-the-docu

Reference: https://blog.csdn.net/qq_22073849/article/details/88964444

in the path

 ~/.vim/plugged/YouCompleteMe

I am in ~/.vim/bundle/youCompleteMe

next execution

/usr/bin/python install.py

If the python version is wrong, change to a newer version (I use anaconda to install directly)