尝试安装openCV lib，第一步是安装cmake，但是当我
sudo apt-get install cmake
我收到
The following packages have unmet dependencies:
cmake : Depends: libjsoncpp0 but it is not installable
E: Unable to correct problems, you have held broken packages.
我已经安装了build-essential, libjsoncpp-dev, pkg-config...等
错误在哪里？