leetcode1046

import heapq
class Solution:
    def lastStoneWeight(self, stones: 'List[int]') -> int:
        heapq._heapify_max(stones)
        #r = [heapq._heappop_max(stones) for _ in range(len(stones))]
        
        while len(stones) >= 2:
            top = heapq._heappop_max(stones)
            top2 = heapq._heappop_max(stones)
            left = abs(top-top2)
            if left != 0:
                heapq.heappush(stones, left)
                heapq._heapify_max(stones)
        if len(stones) == 1:
            last = heapq._heappop_max(stones)
            return last
        else:
            return 0