Max Area of Island

Similar question to number of islands, but here we count the area as how many times we pop from the queue.

from collections import deque

class Solution:
    def maxAreaOfIsland(self, grid: List[List[int]]) -> int:
        if not grid:
            return 0

        m_rows = len(grid)
        n_cols = len(grid[0])
        max_area = 0
        marked = set()

        def bfs(row, col):
            queue = deque()
            queue.append((row, col))
            marked.add((row, col))
            area = 0

            dirs = [(1, 0), (0, 1), (0, -1), (-1, 0)]
            while queue: 
                r, c = queue.popleft()
                area += 1

                for d in dirs:
                    dr, dc = r + d[0], c + d[1]

                    if (0 <= dr < m_rows and
                        0 <= dc < n_cols and
                        grid[dr][dc] == 1 and
                        (dr, dc) not in marked): 
                        queue.append((dr, dc))
                        marked.add((dr, dc))

            return area

        for row in range(m_rows):
            for col in range(n_cols):
                if grid[row][col] == 1 and (row, col) not in marked:
                    area = bfs(row, col)
                    max_area = max(max_area, area)
        
        return max_area