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Solution: The K Weakest Rows in a Matrix

Explore an efficient algorithm to identify the k weakest rows in a binary matrix. Learn to apply binary search to count soldiers in each row and use a max-heap to manage the weakest rows based on soldier count and row index, allowing you to solve this problem effectively.

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Statement

You are given an m×nm \times n binary matrix of 11’s (representing soldiers) and 00’s (representing civilians). The soldiers are positioned in front of the civilians, i.e., all the 11’s will appear to the left of all the 00’s in each row.

A row ii is weaker than a row jj if any of the following is TRUE:

  • The number of soldiers in row ii is less than the number of soldiers in row jj.

  • Both rows have the same number of soldiers and  ...