<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>

 #pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
static const bool __boost = []() {
	cin.tie(nullptr);
	cout.tie(nullptr);
	return std::ios_base::sync_with_stdio(false);
	}();


const size_t BUFFER_SIZE = 0x6fafffff;
alignas(std::max_align_t) char buffer[BUFFER_SIZE];
size_t buffer_pos = 0;
void* operator new(size_t size) {
	constexpr std::size_t alignment = alignof(std::max_align_t); // Default maximum alignment
	size_t padding = (alignment - (buffer_pos % alignment)) % alignment;
	size_t total_size = size + padding;
	char* aligned_ptr = &buffer[buffer_pos + padding];
	buffer_pos += total_size;
	return aligned_ptr;
}
void operator delete(void* ptr) {
}

// Overload the delete[] operator to do nothing
void operator delete[](void* ptr) {}

#include <execution>

class Solution {
public:
    void dfs(int i, int j, vector<vector<int>>& grid, int& currArea, int& maxArea)
    {
        if (i >= grid.size() || j >= grid[0].size())
            return;

        if (grid[i][j] == 0)
            return;

        grid[i][j] = 0;
        ++currArea;

        dfs(i + 1, j, grid, currArea, maxArea);
        dfs(i - 1, j, grid, currArea, maxArea);
        dfs(i, j + 1, grid, currArea, maxArea);
        dfs(i, j - 1, grid, currArea, maxArea);

        maxArea = std::max(maxArea, currArea);
    }

    int maxAreaOfIsland(vector<vector<int>>& grid) {
        int maxArea = 0;
        for (int i = 0; i < grid.size(); i++)
            for (int j = 0; j < grid[i].size(); j++)
                if (grid[i][j] == 1)
                {
                    int currArea = 0;
                    dfs(i, j, grid, currArea, maxArea);
                }
        return maxArea;
    }
};
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