Rotate Image

**Problem Statement:** You are 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. **Hint / Expected Approach:** Transpose then reverse rows **Edge Cases to Consider:** - (1) 1×1 matrix - (2) 2×2 matrix - (3) Already rotated image

Examples

Example 1

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

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

Example 2

Input: [[5,1,9,11],[2,4,8,10],[13,3,6,7],[15,14,12,16]]

Output: [[15,13,2,5],[14,3,4,1],[12,6,8,9],[16,7,10,11]]

Example 3

Input: [[1]]

Output: [[1]]

Constraints

▪1 <= nums.length <= 10^4
▪-10^9 <= nums[i] <= 10^9
▪Time complexity should be O(n) or O(n log n)

Watch Out For Edge Cases

▪1×1 matrix
▪2×2 matrix
▪Already rotated image

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