Process to import Company and Contact CSV

Hi.  I would like to understand how to import a CSV that has Company and Contact details in each row.    I have two tables in my database; Company and Contacts.   In the contacts table there is a look up to which company the contacts work for.  So in the company table I have only one copy of the company.   Question is how do I import multiple employees that work for one company.  Eg.

Ninox John Smith

Ninox Tony Winter

Ninox Max Verstappen

Ninox Nikko Hulkenburg

When I import this I want to end up with one new Company "Ninox" record and four Contact records.   

The underlying reason I want this is that I have companies that have maybe 100 Contacts which I need to import but I need a database where I can change the Company name or address only once so I don't have to update 100 contacts.   However, can't see how to import these records.