<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>

int checkit(int row,int col,vector<vector<int>>&grid)
{
     int n=grid.size();
     int m=grid[0].size();

        int area=1;
    if( row<n && row>=0 && col<m && col>=0 &&  grid[row][col]==1 )
    {
        
        grid[row][col]=0;
        area+=checkit(row+1,col,grid);
        area+=checkit(row-1,col,grid);
        area+=checkit(row,col+1,grid);
        area+=checkit(row,col-1,grid);
    }
    else
    {
        return 0;
    }
    return area;
}

class Solution {
public:
    int maxAreaOfIsland(vector<vector<int>>& grid) {

        int n=grid.size();
        int m=grid[0].size();
        int maxc=0;

        for(int i=0;i<n;i++)
        {
            for(int j=0;j<m;j++)
            {
                int c=checkit(i,j,grid);
                if(c>maxc)
                maxc=c;
            }
        }
        return maxc;
    }
};
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