I have to install the latest version of R on my Linux Mint 19 computer in order to run some bioinformatics tools (Biostrings). I then followed this website for the tutorial (I suppose things are not very different with Mint or Ubuntu after all). However, after I typed in the third command line into the Terminal, which is
sudo add-apt-repository 'deb https://cloud.r-project.org/bin/linux/ubuntu bionic-cran35/'
it replied
Malformed input, repository not added.
Now I understood that there is a typo in the command on the website, and I myself corrected it to
sudo add-apt-repository 'deb https://cloud.r-project.org/bin/linux/ubuntu/bionic-cran35/'
However, the problem still exists.
Could anyone help me with this issue?