执行命令如下：
cd opencv-3.4.5
cd build
sudo make uninstall
cd ..
sudo rm -rf build
sudo rm -r \
/usr/local/include/opencv\
/usr/local/include/opencv2 \
/usr/include/opencv \
/usr/include/opencv2 \
/usr/local/bin/opencv* \
/usr/local/lib/libopencv* \
/usr/local/share/opencv \
/usr/local/share/OpenCV \
/usr/share/opencv \
/usr/share/OpenCV ![sudo apt-get update 出错 Updating from such a repository can‘t be done securely, and is therefore[图]](data:image/gif;base64,R0lGODlhAQABAIAAAP///wAAACwAAAAAAQABAAACAkQBADs=)