Rotate Matrix Regions Around the Diagonals
Susquehanna International Group (SIG)● MediumNEW GRADOAProblem statement
You are given an n x n integer matrix and an integer turns. The main diagonal and anti-diagonal divide the cells outside the diagonals into top, right, bottom, and left regions.
One turn rotates those four regions clockwise by 90 degrees: every non-diagonal value at (row, column) moves to (column, n - 1 - row). Every cell on either diagonal stays fixed.
Apply exactly turns turns and return the resulting matrix.
Function
rotateMatrixOverDiagonals(matrix: int[][], turns: int) → int[][]Examples
Example 1
matrix = [[1,2,3,4,5],[2,1,9,6,3],[7,0,4,8,1],[5,2,4,1,9],[6,4,3,2,1]]turns = 1return = [[1,5,7,2,5],[4,1,0,6,2],[3,4,4,9,3],[2,2,8,1,4],[6,9,1,3,1]]The diagonal values remain in place. Every other value advances clockwise into the next triangular region.
Example 2
matrix = [[1,2,3],[4,5,6],[7,8,9]]turns = 1return = [[1,4,3],[8,5,2],[7,6,9]]The four off-diagonal values 2, 6, 8, 4 move clockwise, while 1, 3, 5, 7, 9 stay fixed.
Example 3
matrix = [[7]]turns = 3return = [[7]]The only cell lies on both diagonals, so every turn leaves it unchanged.
Constraints
1 <= n <= 200.matrix.length = matrix[i].length = n.-10^9 <= matrix[i][j] <= 10^9.1 <= turns <= 4.