<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> </p> <p><strong>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>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>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> </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 <= m, n <= 60</code></li> <li><code>1 <= targetGrid[row][col] <= 60</code></li> </ul>