Rotate Image

Medium · Math & Geometry

You are given a square grid of integers representing an image. Rotate the grid 90 degrees clockwise, modifying it directly without allocating a separate grid for the result. Return nothing.

Examples

Input:  matrix = [[1,2,3],[4,5,6],[7,8,9]]
Output: [[7,4,1],[8,5,2],[9,6,3]]
Why:    Each layer of the square is rotated clockwise by shifting its four sides.

Input:  matrix = [[1,2],[3,4]]
Output: [[3,1],[4,2]]
Why:    The 2x2 grid rotates so the first column becomes the first row in reverse.

Input:  matrix = [[1]]
Output: [[1]]
Why:    A single cell is unchanged by rotation.

Constraints

1 <= n <= 20, -1000 <= matrix[i][j] <= 1000, where matrix is an n x n grid

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Practise Rotate Image

This statement is written for CodeSpeek. The problem is part of the NeetCode 150 list; Watch NeetCode's explanation of Rotate Image. Reference solutions from the NeetCode repository (MIT) are used to verify our tests.