Brick Wall LeetCode solution in Python

1
class Solution:
2
    def leastBricks(self, wall: List[List[int]]) -> int:
3
        m = len(wall)
4
        ctr = {}
5
        res = m
6
        for i in range(m):
7
            n = len(wall[i])
8
            curr = 0
9
            for j in range(n - 1):
10
                curr += wall[i][j]
11
                x = ctr.get(curr, m) - 1
12
                ctr[curr] = x
13
                res = min(res, x)
14
        return res