Error installing Ros Melodic

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I'm trying to install ROS Melodic on Linux Mint (based on Ubuntu bionic). I have configured my Ubuntu repositories and I have followed the installation guide. Should I install any package before ros melodic?

The error is the following, I am dealing with unmet dependencies:

Reading package lists... Done
Building dependency tree       
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 ros-melodic-desktop : Depends: ros-melodic-common-tutorials but it is not going to be installed
                       Depends: ros-melodic-geometry-tutorials but it is not going to be installed
                       Depends: ros-melodic-robot but it is not going to be installed
                       Depends: ros-melodic-ros-tutorials but it is not going to be installed
                       Depends: ros-melodic-urdf-tutorial but it is not going to be installed
                       Depends: ros-melodic-visualization-tutorials but it is not going to be installed
                       Depends: ros-melodic-viz but it is not going to be installed
E: Unable to correct problems, you have held broken packages.