Did not understand the solution properly

I did not understand the solution of this problem completely, like i do have some idea after reading this(https://www.geeksforgeeks.org/combinatorial-game-theory-set-2-game-nim/)

but still how it is working in this problem i could not get completely.

Let prime numbers are piles of stones and their total prime powers in array are equivalent to respective piles size. Now this has become a problem where two players are playing optimally and they reduce every pile to size 0. The last player unable to move loses.

I hope I’ve cleared your doubt. I ask you to please rate your experience here
Your feedback is very important. It helps us improve our platform and hence provide you
the learning experience you deserve.

On the off chance, you still have some questions or not find the answers satisfactory, you may reopen
the doubt.