Algoverse_adesh_24

class Solution:
    def surfaceArea(self, grid: List[List[int]]) -> int:
        n = len(grid)
        res = 0
        for i in range(n):
            rh = 0
            ch = 0
            for j in range(n):
                t = grid[i][j]
                res += 2 if t else 0
                res += abs(t - rh)
                rh = t
                t = grid[j][i]
                res += abs(t - ch)
                ch = t
            res += rh + ch
        return res