<p>There is a strange printer with the following two special requirements:</p>

<ul>
	<li>On each turn, the printer will print a solid rectangular pattern of a single color on the grid. This will cover up the existing colors in the rectangle.</li>
	<li>Once the printer has used a color for the above operation, <strong>the same color cannot be used again</strong>.</li>
</ul>

<p>You are given a <code>m x n</code> matrix <code>targetGrid</code>, where <code>targetGrid[row][col]</code> is the color in the position <code>(row, col)</code> of the grid.</p>

<p>Return <code>true</code><em> if it is possible to print the matrix </em><code>targetGrid</code><em>,</em><em> otherwise, return </em><code>false</code>.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2021/12/23/print1.jpg" style="width: 600px; height: 175px;" />
<pre>
<strong>Input:</strong> targetGrid = [[1,1,1,1],[1,2,2,1],[1,2,2,1],[1,1,1,1]]
<strong>Output:</strong> true
</pre>

<p><strong class="example">Example 2:</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2021/12/23/print2.jpg" style="width: 600px; height: 367px;" />
<pre>
<strong>Input:</strong> targetGrid = [[1,1,1,1],[1,1,3,3],[1,1,3,4],[5,5,1,4]]
<strong>Output:</strong> true
</pre>

<p><strong class="example">Example 3:</strong></p>

<pre>
<strong>Input:</strong> targetGrid = [[1,2,1],[2,1,2],[1,2,1]]
<strong>Output:</strong> false
<strong>Explanation:</strong> It is impossible to form targetGrid because it is not allowed to print the same color in different turns.
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>m == targetGrid.length</code></li>
	<li><code>n == targetGrid[i].length</code></li>
	<li><code>1 &lt;= m, n &lt;= 60</code></li>
	<li><code>1 &lt;= targetGrid[row][col] &lt;= 60</code></li>
</ul>

class Solution {
public:
    vector<vector<int>>mat;
    bool dfs(int node,vector<int>&vis,map<int,set<int>>&mp){
        vis[node]=2;
        for(auto adjNode:mp[node]){
            if(vis[adjNode]==0){
                if(dfs(adjNode,vis,mp))
                    return true;
            }
            else if(vis[adjNode]==2)
                return true;
        }
        vis[node]=1;
        return false;
    }
    bool isPrintable(vector<vector<int>>& grid) {
        mat=grid;
        int maxi=0;
        set<int>st;
        map<int,set<int>>mp;
        int n=mat.size();
        int m=mat[0].size();

        for(int i=0;i<n;i++)
            for(int j=0;j<m;j++)
                st.insert(mat[i][j]);
        
        for(auto &it:st){ 
            int currVal=it;
            maxi=max(maxi,currVal);
            int lt=1e9,rt=1e9,lb=-1e9,rb=-1e9;
            for(int i=0;i<n;i++){
                for(int j=0;j<m;j++){
                    if(currVal==mat[i][j]){
                        lt=min(lt,i);
                        rt=min(rt,j);
                        lb=max(lb,i);
                        rb=max(rb,j);
                    }
                }
            }
 

            for(int i=lt;i<=lb;i++){
                for(int j=rt;j<=rb;j++){ 
                    if(currVal!=mat[i][j]){
                        mp[currVal].insert(mat[i][j]);
                    }
                }
            }
        }   
        vector<int>vis(maxi+1,0); 
        for(int i=0;i<vis.size();i++){
            if(vis[i]==0){
                if(dfs(i,vis,mp))
                    return false;
            }
        }
        return true;
    }
};
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