<p>You are given an <code>m x n</code> binary matrix <code>grid</code>, where <code>0</code> represents a sea cell and <code>1</code> represents a land cell.</p>

<p>A <strong>move</strong> consists of walking from one land cell to another adjacent (<strong>4-directionally</strong>) land cell or walking off the boundary of the <code>grid</code>.</p>

<p>Return <em>the number of land cells in</em> <code>grid</code> <em>for which we cannot walk off the boundary of the grid in any number of <strong>moves</strong></em>.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2021/02/18/enclaves1.jpg" style="width: 333px; height: 333px;" />
<pre>
<strong>Input:</strong> grid = [[0,0,0,0],[1,0,1,0],[0,1,1,0],[0,0,0,0]]
<strong>Output:</strong> 3
<strong>Explanation:</strong> There are three 1s that are enclosed by 0s, and one 1 that is not enclosed because its on the boundary.
</pre>

<p><strong class="example">Example 2:</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2021/02/18/enclaves2.jpg" style="width: 333px; height: 333px;" />
<pre>
<strong>Input:</strong> grid = [[0,1,1,0],[0,0,1,0],[0,0,1,0],[0,0,0,0]]
<strong>Output:</strong> 0
<strong>Explanation:</strong> All 1s are either on the boundary or can reach the boundary.
</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;= 500</code></li>
	<li><code>grid[i][j]</code> is either <code>0</code> or <code>1</code>.</li>
</ul>

class Solution:
    def numEnclaves(self, grid: List[List[int]]) -> int:

        enclaves = 0 
        rows = len(grid)
        cols = len(grid[0])


        visited = set() 



        def isMove(r,c):
            return 0 <= r < rows and 0 <= c < cols and grid[r][c] == 1 and (r,c) not in visited


        def dfs(r, c):
            # Marks the cell as visited and changes it temporarily to 'V'
            visited.add((r, c))
            grid[r][c] = 0

            # Possible movements: down, right, left, up
            directions = [(1, 0), (0, 1), (0, -1), (-1, 0)]

            for dr, dc in directions:
                new_row = r + dr
                new_col = c + dc

                if isMove(new_row, new_col):
                    dfs(new_row, new_col)

        for i in range(rows):
            if grid[i][0] == 1 and isMove(i,0):
                dfs(i, 0)
            if grid[i][cols - 1] == 1 and isMove(i,cols-1):
                dfs(i, cols - 1)

        
        for j in range(cols):
            if grid[0][j] == 1 and isMove(0,j):
                dfs(0, j)
            if grid[rows - 1][j] ==1 and isMove(rows-1,j):
                dfs(rows - 1, j)
        


 



        for i in range(rows):
            for j in range(cols):
                if grid[i][j] == 1:
                    enclaves+=1
        
        return enclaves

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