<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>>& grid) {
        int m=grid.size();
        int n=grid[0].size();
        map<int,pair<int,int>> color_min_coords;
        map<int,pair<int,int>> color_max_coords;
        
        set<int> colors;
        for(int i=0;i<m;i++){
            for(int j=0;j<n;j++){
                colors.insert(grid[i][j]);
            }
        }
        
        for(auto color:colors){
            int min_row=1e9,min_col=1e9,max_row=-1,max_col=-1;
            for(int i=0;i<m;i++){
                for(int j=0;j<n;j++){
                    if(grid[i][j]==color){
                        min_row=min(min_row,i);
                        max_row=max(max_row,i);
                        
                        min_col=min(min_col,j);
                        max_col=max(max_col,j);
                    }
                }
            }
            color_min_coords[color]={min_row,min_col};
            color_max_coords[color]={max_row,max_col};
        }
        
        map<int,int> indegree;
        map<int,vector<int>> graph;
        for(auto color:colors){
            bool isRectangle=true;
            int sr=color_min_coords[color].first,sc=color_min_coords[color].second;
            int dr=color_max_coords[color].first,dc=color_max_coords[color].second;
            set<int> overlap_colors;
            for(int i=sr;i<=dr;i++){
                for(int j=sc;j<=dc;j++){
                    if(grid[i][j] != color){
                        isRectangle=false;
                        overlap_colors.insert(grid[i][j]);
                    }
                    
                }
            }
            if(!isRectangle){
                for(auto top_color:overlap_colors){
                    graph[top_color].push_back(color);
                    indegree[color]++;
                }
            }else{
                indegree[color]=0;
            }
        }
        
        queue<int> q;
        vector<int> vis_colors;
        for(auto i:indegree){
            if(i.second==0){
                q.push(i.first);
                vis_colors.push_back(i.first);
            }
        }
        
        while(!q.empty()){
            int node=q.front();
            q.pop();
            
            for(auto c:graph[node]){
                indegree[c]--;
                if(indegree[c]==0){
                    q.push(c);
                    vis_colors.push_back(c);
                }
            }
        }
        if(vis_colors.size()==colors.size()) return true;
        return false;
        
        
    }
};
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