Copying different files from different folders

Question

I have 400 folders (/123_0/, /123_1/, ...) and inside each one I have a file with extension *.root and different names. I just want to copy these files to a destination /destination/. How can I do it?

Answer 1

If all those 400 folders are in the same location, here is how you can do it:

cp **/*.root destination/