HJ-Split Tutorial
So this post would talking about how to combine the split episodes part.

Press here to download HJsplit (original link from website)
download
Unzip it and run the application.
You should have the 3 files for one episode in the same folder then press input file and select the file with .001. You can press change the output folder to anyway.
Once youre done you should see this popup
And you're ready to watch! Enjoy!