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Only if you backed up your networks ahead of time.  Otherwise you have to start over from scratch.

I didn't know either but I did a little research because I didn't want to lose my networks when I restored my laptop.

I found this in the Hamachi FAQ on their website.

To back up your Hamachi configuration
Ensure you are running the latest version
Launch Hamachi, open Preferences and go to System
Click on Open Hamachi Configuration Folder button
Copy all files and folders fCopy all files and folders from an open window to some place safe

When you install Hamachi on the new computer, do not go Online.

Go to Hamachi Preferences > System > Open Hamachi Configuration Folder. 
In here, you will paste the configuration files. 
When the computer is put online in Hamachi, it will retain its old identity.
If you did not make a backup, and cannot get the files back