<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:
    bool isPrintable(vector<vector<int>>& t) {
        vector<int>xmin(61,INT_MAX);
        vector<int>ymin(61,INT_MAX);
        vector<int>ymax(61,-1);
        vector<int>xmax(61,-1);
        int n=t.size();
        int m=t[0].size();
        map<int,int>mp;
       for(int i=0;i<n;i++){
        for(int j=0;j<m;j++){
            mp[t[i][j]]++;
            xmin[t[i][j]]=min(xmin[t[i][j]],i);
            xmax[t[i][j]]=max(xmax[t[i][j]],i);
            ymin[t[i][j]]=min(ymin[t[i][j]],j);
            ymax[t[i][j]]=max(ymax[t[i][j]],j);
            
        }
       }
       queue<int>q;
       vector<int>indegree(61,0);
       vector<vector<int>>v(61);
       for(auto it:mp){
       for(int i=xmin[it.first];i<=xmax[it.first];i++){
        for(int j=ymin[it.first];j<=ymax[it.first];j++){
         if(t[i][j]!=it.first){
            indegree[t[i][j]]++;
            v[it.first].push_back(t[i][j]);
         }
        }
       }
       }
     for(int i=1;i<=60;i++){
        if(mp.find(i)!=mp.end() && indegree[i]==0){
        q.push(i);
        }
     }
     int cnt=0;
     while(!q.empty()){
        int top=q.front();
        q.pop();
        cnt++;
        for(int i=0;i<v[top].size();i++){
            indegree[v[top][i]]--;
            if(indegree[v[top][i]]==0){
                q.push(v[top][i]);
            }
        }
     }
     if(cnt==mp.size()){
        return true;
     }
     return false;
    }
};
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