Sort Matrix by Diagonals
You receive an n x n square matrix of integers grid. Produce the matrix such that:
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The diagonals in the bottom-left triangle (including the middle diagonal) are sorted in non-increasing order.
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The diagonals in the top-right triangle are sorted in non-decreasing order.
Input: grid = [[1,7,3],[9,8,2],[4,5,6]]
Output: [[8,2,3],[9,6,7],[4,5,1]]
Explanation: The diagonals with a black arrow (bottom-left triangle) should be sorted in non-increasing order:
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[1, 8, 6]becomes[8, 6, 1]. -
[9, 5]and[4]remain unchanged.
The diagonals with a blue arrow (top-right triangle) should be sorted in non-decreasing order:
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[7, 2]becomes[2, 7]. -
[3]remains unchanged.
Input: grid = [[0,1],[1,2]]
Output: [[2,1],[1,0]]
Explanation: The diagonals with a black arrow must be non-increasing, so [0, 2] is changed to [2, 0]. The other diagonals are already in the correct order.
Input: grid = [[1]]
Output: [[1]]
Explanation: Diagonals with exactly one element are already in order, so no changes are needed.
Constraints
grid.length == grid[i].length == n1 <= n <= 10-10^5 <= grid[i][j] <= 10^5
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