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			39 lines
		
	
	
		
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			39 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			HTML
		
	
	
	
	
	
| <p>You are given an <code>n x n</code> integer <code>matrix</code>. You can do the following operation <strong>any</strong> number of times:</p>
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| 
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| <ul>
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| 	<li>Choose any two <strong>adjacent</strong> elements of <code>matrix</code> and <strong>multiply</strong> each of them by <code>-1</code>.</li>
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| </ul>
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| 
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| <p>Two elements are considered <strong>adjacent</strong> if and only if they share a <strong>border</strong>.</p>
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| 
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| <p>Your goal is to <strong>maximize</strong> the summation of the matrix's elements. Return <em>the <strong>maximum</strong> sum of the matrix's elements using the operation mentioned above.</em></p>
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| 
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| <p> </p>
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| <p><strong class="example">Example 1:</strong></p>
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| <img alt="" src="https://assets.leetcode.com/uploads/2021/07/16/pc79-q2ex1.png" style="width: 401px; height: 81px;" />
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| <pre>
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| <strong>Input:</strong> matrix = [[1,-1],[-1,1]]
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| <strong>Output:</strong> 4
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| <b>Explanation:</b> We can follow the following steps to reach sum equals 4:
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| - Multiply the 2 elements in the first row by -1.
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| - Multiply the 2 elements in the first column by -1.
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| </pre>
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| 
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| <p><strong class="example">Example 2:</strong></p>
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| <img alt="" src="https://assets.leetcode.com/uploads/2021/07/16/pc79-q2ex2.png" style="width: 321px; height: 121px;" />
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| <pre>
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| <strong>Input:</strong> matrix = [[1,2,3],[-1,-2,-3],[1,2,3]]
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| <strong>Output:</strong> 16
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| <b>Explanation:</b> We can follow the following step to reach sum equals 16:
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| - Multiply the 2 last elements in the second row by -1.
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| </pre>
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| 
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| <p> </p>
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| <p><strong>Constraints:</strong></p>
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| 
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| <ul>
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| 	<li><code>n == matrix.length == matrix[i].length</code></li>
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| 	<li><code>2 <= n <= 250</code></li>
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| 	<li><code>-10<sup>5</sup> <= matrix[i][j] <= 10<sup>5</sup></code></li>
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| </ul>
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