<p>You are given an <code>m x n</code> binary grid <code>grid</code> where <code>1</code> represents land and <code>0</code> represents water. An <strong>island</strong> is a maximal <strong>4-directionally</strong> (horizontal or vertical) connected group of <code>1</code>&#39;s.</p>

<p>The grid is said to be <strong>connected</strong> if we have <strong>exactly one island</strong>, otherwise is said <strong>disconnected</strong>.</p>

<p>In one day, we are allowed to change <strong>any </strong>single land cell <code>(1)</code> into a water cell <code>(0)</code>.</p>

<p>Return <em>the minimum number of days to disconnect the grid</em>.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2021/12/24/land1.jpg" style="width: 500px; height: 169px;" />
<pre>
<strong>Input:</strong> grid = [[0,1,1,0],[0,1,1,0],[0,0,0,0]]

<strong>Output:</strong> 2
<strong>Explanation:</strong> We need at least 2 days to get a disconnected grid.
Change land grid[1][1] and grid[0][2] to water and get 2 disconnected island.
</pre>

<p><strong class="example">Example 2:</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2021/12/24/land2.jpg" style="width: 404px; height: 85px;" />
<pre>
<strong>Input:</strong> grid = [[1,1]]
<strong>Output:</strong> 2
<strong>Explanation:</strong> Grid of full water is also disconnected ([[1,1]] -&gt; [[0,0]]), 0 islands.
</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;= 30</code></li>
	<li><code>grid[i][j]</code> is either <code>0</code> or <code>1</code>.</li>
</ul>

class Solution:
    def minDays(self, grid: List[List[int]]) -> int:
        
        def isConnected(k,v,grid,visited):
            visited[k][v] = 1
            if k+1<len(grid) and grid[k+1][v]==1 and visited[k+1][v]!=1:
                isConnected(k+1,v,grid,visited)
            if v+1<len(grid[0]) and grid[k][v+1]==1 and visited[k][v+1]!=1:
                isConnected(k,v+1,grid,visited)
            if k-1>=0 and grid[k-1][v]==1 and visited[k-1][v]!=1:
                isConnected(k-1,v,grid,visited)
            if v-1>=0 and grid[k][v-1]==1 and visited[k][v-1]!=1:
                isConnected(k,v-1,grid,visited)
        def _countIslands():
            visited = [[0 for _ in range(len(grid[0]))] for _ in range(len(grid))]
            cnt = 0
            for i in range(len(grid)):
                for j in range(len(grid[0])):
                    if grid[i][j]==1 and visited[i][j]!=1:
                        isConnected(i,j,grid,visited)
                        cnt+=1
            return cnt
        if _countIslands()!=1:
            return 0
        
        for i in range(len(grid)):
            for j in range(len(grid[0])):
                if grid[i][j] == 1:
                    grid[i][j]=0
                    if _countIslands()!=1:
                        return 1
                    grid[i][j]=1
        return 2
        
        
        
542