class Solution(object):
    def leastBricks(self, wall):
        """
        :type wall: List[List[int]]
        :rtype: int
        """
        ht = len(wall)
        wt = sum(wall[0])
        d = {}

        for row in wall:
            tot = 0
            for brick in row:
                tot += brick
                if tot < wt:
                    if tot in d:
                        d[tot] -= 1
                    else:
                        d[tot] = ht - 1
        
        l = list(d.values())
        l.append(ht)
        return min(l)