这道题目是一个01背包，背包可承受质量为总质量的一半，然后找到这个质量就可以了

class Solution:
    def lastStoneWeightII(self, stones: List[int]) -> int:
        n = len(stones)
        s = sum(stones)/2
        dp = {0}
        for i in range(n):
            dp |= {stones[i] + c if stones[i] + c <= s else c for c in dp}

        return int((s-max(dp))*2)