Given a m * n
matrix mat
of integers, sort it
diagonally in ascending order from the top-left to the bottom-right then return the
sorted array.
Example 1:
Input: mat = [[3,3,1,1],[2,2,1,2],[1,1,1,2]] Output: [[1,1,1,1],[1,2,2,2],[1,2,3,3]]
Constraints:
m == mat.length
n == mat[i].length
1 <= m, n <= 100
1 <= mat[i][j] <= 100