<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 {
public:
    
    void isLands(int i, int j, vector<vector<int>>& grid, vector<int> &row, vector<int> &col)
    {
        grid[i][j]=-1;


        for(int k=0;k<4;k++)
        {
            int x1=i+row[k];
            int y1=j+col[k];

            if(x1>=0 && y1>=0 && x1<grid.size() && y1<grid[0].size() && grid[x1][y1]==1)
            {
                isLands(x1,y1,grid,row,col);

            }

        } 

        return;
 

    }

    bool countIslands(vector<vector<int>  > grid)
    {

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

     vector<int> row={1,0,-1,0};
     vector<int> col={0,1,0,-1};

     int ans=0;



    for(int i=0;i<n;i++)
     {
        for(int j=0;j<m;j++)
        {
            if(grid[i][j]==1)
            {
                ans++;
                isLands(i,j,grid,row,col);
            }
        }
     }

     cout<<ans<<endl;


     if(ans==1)
     {
        return false;
     }


     return true;
    }



    bool solve(int k, vector<vector<int> > grid)
    {

        if(countIslands(grid)==true)
        {
            return true;
        }

        if(k==0)
        {
            return false;
        }


        for(int i=0;i<grid.size();i++)
        {
            for(int j=0;j<grid[0].size();j++)
            {
                if(k>=1 && grid[i][j]==1)
                {
                    grid[i][j]=0;
                    if(solve(k-1,grid))
                    {
                        return true;
                    }

                    grid[i][j]=1;


                }
            }
        } 

        return false;


    }


    int minDays(vector<vector<int>>& grid) {
        

     int k=0;   

     while(k<=2)
     {

        if(solve(k,grid)==true)
        {
            return k;
        }
        k++;

     } 




     return -1;




    }
};
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