695. Max Area of Island

 1class Solution:
 2    def maxAreaOfIsland(self, grid: List[List[int]]) -> int:
 3        if not grid or not grid[0]:
 4            return 0
 5
 6        result = 0
 7        m, n = len(grid), len(grid[0])
 8        directions = ((1, 0), (-1, 0), (0, 1), (0, -1))
 9
10        for i in range(m):
11            for j in range(n):
12                if grid[i][j] == 1:
13                    grid[i][j] = 0
14                    island_area = 0
15                    dq = deque([(i, j)])
16                    while dq:
17                        ci, cj = dq.popleft()
18                        island_area += 1
19
20                        for di, dj in directions:
21                            ni, nj = ci + di, cj + dj
22                            if 0 <= ni < m and 0 <= nj < n and grid[ni][nj] == 1:
23                                grid[ni][nj] = 0
24                                dq.append((ni, nj))
25
26                    result = max(result, island_area)
27
28        return result