How to find MULTIPLE duplicated elements that meet the criteria?

I have an array, full of numbers including ones that are duplicated.

An example would be: 1, 2, 2, 3, 4, 5, 5, 6, 7, 8, 9, 9, 9, 9, 10

I want to find numbers that are duplicated exactly two times, regardless of the number itself.

What would be needed to go about this idea?

https://stackoverflow.com/questions/67014027/how-to-find-multiple-duplicated-elements-that-meet-the-criteria April 09, 2021 at 09:47AM