Rotate Matrix

ArrayMatrix

Given an n x n 2D matrix representing an image, rotate the image by 90 degrees (clockwise). You have to rotate the image in-place, which means you have to modify the input 2D matrix directly without using another 2D matrix.

Example 1

Input

Output

[[3,1],[4,2]]

Explanation. Rotating the matrix [[1,2],[3,4]] 90 degrees clockwise results in [[3,1],[4,2]].

Example 2

Input

Output

[[7,4,1],[8,5,2],[9,6,3]]

Explanation. Rotating the matrix [[1,2,3],[4,5,6],[7,8,9]] 90 degrees clockwise results in [[7,4,1],[8,5,2],[9,6,3]].

Example 3

Input

[
  [
    1
  ]
]

Output

[[1]]

Explanation. A 1x1 matrix rotated 90 degrees remains the same.

Follow-up: Can you perform this operation in other directions like 90 degrees counterclockwise or 180 degrees?

Constraints:

1. The given matrix will be of size n x n, where n is greater than 0. 2. You must rotate the matrix in-place; using extra space for another matrix is not allowed.

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