How to only grep one of each address. Linux
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Okay so lets say I have a list of addresses in a text file like this:

    https://www.amazon.com
    https://www.google.com
    https://www.msn.com
    https://www.google.com
    https://www.netflix.com
    https://www.amazon.com
    ...

There is a whole bunch of other stuff there but basically the issue I am having is that after running this:

`grep "https://" addresses.txt | cut -d"/" -f3 `

I get amazon.com and google.com twice. I want to only get them once. I don't know how to make the search only grep for things that are unique.