<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:
        
        row, col = len(grid), len(grid[0])
        visited = set()
        max_size = 0

        def bfs(r, c):
            q = deque()
            destinations = [[1,0], [-1, 0], [0, 1], [0, -1]]
            q.append((r, c))
            current_size = 1
            while q:
                r, c =  q.popleft()
                for dr, dc in destinations:
                    if (r + dr in range(row) and 
                    c + dc in range(col) and
                    grid[r + dr][c + dc] == 1 and
                    (r + dr, c + dc) not in visited):
                        visited.add((r + dr, c + dc))
                        current_size += 1
                        q.append((r + dr, c + dc))

            return current_size

        for r in range(row):
            for c in range(col):
                current_size = 0
                if (grid[r][c] == 1 and 
                    (r, c) not in visited):
                    
                    visited.add((r, c))
                    current_size = bfs(r, c)
                
                max_size = max(current_size, max_size)
        
        return max_size


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