<p>You are given an <code>m x n</code> binary matrix <code>grid</code>. An island is a group of <code>1</code>&#39;s (representing land) connected <strong>4-directionally</strong> (horizontal or vertical.) You may assume all four edges of the grid are surrounded by water.</p>

<p>The <strong>area</strong> of an island is the number of cells with a value <code>1</code> in the island.</p>

<p>Return <em>the maximum <strong>area</strong> of an island in </em><code>grid</code>. If there is no island, return <code>0</code>.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2021/05/01/maxarea1-grid.jpg" style="width: 500px; height: 310px;" />
<pre>
<strong>Input:</strong> grid = [[0,0,1,0,0,0,0,1,0,0,0,0,0],[0,0,0,0,0,0,0,1,1,1,0,0,0],[0,1,1,0,1,0,0,0,0,0,0,0,0],[0,1,0,0,1,1,0,0,1,0,1,0,0],[0,1,0,0,1,1,0,0,1,1,1,0,0],[0,0,0,0,0,0,0,0,0,0,1,0,0],[0,0,0,0,0,0,0,1,1,1,0,0,0],[0,0,0,0,0,0,0,1,1,0,0,0,0]]
<strong>Output:</strong> 6
<strong>Explanation:</strong> The answer is not 11, because the island must be connected 4-directionally.
</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> grid = [[0,0,0,0,0,0,0,0]]
<strong>Output:</strong> 0
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>m == grid.length</code></li>
	<li><code>n == grid[i].length</code></li>
	<li><code>1 &lt;= m, n &lt;= 50</code></li>
	<li><code>grid[i][j]</code> is either <code>0</code> or <code>1</code>.</li>
</ul>

class Solution:
    def maxAreaOfIsland(self, grid: List[List[int]]) -> int:
        m = len(grid)
        n = len(grid[0])
        maxarea = 0

        for r in range(m):
            for c in range(n):
                if grid[r][c] == 1:
                    area = 1
                    curmax = area
                    neighbors = []
                    neighbors.append((r, c, area))
                    grid[r][c] = 0

                    while neighbors:
                        i, j, a = neighbors.pop(0)
                        a = max(curmax, a)
                        
                        if i-1 >= 0 and grid[i-1][j] == 1:
                            a += 1
                            grid[i-1][j] = 0
                            neighbors.append((i-1, j, a))
                        if i+1 < m and grid[i+1][j] == 1:
                            a += 1
                            grid[i+1][j] = 0
                            neighbors.append((i+1, j, a))
                        if j-1 >= 0 and grid[i][j-1] == 1:
                            a += 1
                            grid[i][j-1] = 0
                            neighbors.append((i, j-1, a))
                        if j+1 < n and grid[i][j+1] == 1:
                            a += 1
                            grid[i][j+1] = 0
                            neighbors.append((i, j+1, a))
                        curmax = max(curmax, a)
                        maxarea = max(maxarea, curmax)
        return maxarea
16400