Exponential Game

Read problems statements in Russian here Little Chef is trying to learn exponents. He is especially interested in a number raised to the power of itself. Head Chef being his mentor has decided to give him a two player game to play. The game is as follows: You are given n piles of stones. The piles have a_1, a_2 .. a_n number of stones . Each player on his/her turn can remove x number of stones wh