human
Give me a the Python program you requested given the following:
Solve in Python:
Alex and Lee continue their games with piles of stones.  There are a number of piles arranged in a row, and each pile has a positive integer number of stones piles[i].  The objective of the game is to end with the most stones. 
Alex and Lee take turns, with Alex starting first.  Initially, M = 1.
On each player's turn, that player can take all the stones in the first X remaining piles, where 1 <= X <= 2M.  Then, we set M = max(M, X).
The game continues until all the stones have been taken.
Assuming Alex and Lee play optimally, return the maximum number of stones Alex can get.
 
Example 1:
Input: piles = [2,7,9,4,4]
Output: 10
Explanation:  If Alex takes one pile at the beginning, Lee takes two piles, then Alex takes 2 piles again. Alex can get 2 + 4 + 4 = 10 piles in total. If Alex takes two piles at the beginning, then Lee can take all three piles left. In this case, Alex get 2 + 7 = 9 piles in total. So we return 10 since it's larger. 

 
Constraints:

1 <= piles.length <= 100
1 <= piles[i] <= 10 ^ 4
assistant
#Here is the Python program you requested.

class Solution:
    def helper(self, s, M, n):
        if s >= n:
            return 0
        if (s, M) in self.mem:
            return self.mem[(s, M)]
        cur, best = 0, -float('inf')
        for x in range(1, 2*M + 1):
            if s + x > n:
                break
            cur += self.piles[s + x -1]
            best = max(best, cur - self.helper(s + x, max(x, M), n))
        self.mem[(s, M)] = best
        return best
                
        
    def stoneGameII(self, piles: List[int]) -> int:
        n = len(piles)
        self.mem = {}
        self.piles = piles
        return (sum(piles) + self.helper(0, 1, n))//2