---
title: '48. Rotate Image'
description: You are given an n x n 2D matrix representing an image, rotate the image by 90 degrees (clockwise)
sidebar:
  label: 'Rotate Image'
  badge: 'Medium'
---

<Badge variant="accent">Matrix Index Math</Badge>

### Example 1:
- Input: `matrix = [[1,2,3],[4,5,6],[7,8,9]]`
- Output: `[[7,4,1],[8,5,2],[9,6,3]]`

### Example 2:
- Input: `matrix = [[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]]`

### Constraints:

- `n == matrix.length == matrix[i].length`
- `1 <= n <= 20`
- `-1000 <= matrix[i][j] <= 1000`

## Solution

```py
class Solution:
    def rotate(self, matrix: List[List[int]]) -> None:
        n = len(matrix)
        for r in range(n):
            for c in range(r + 1, n):
                matrix[r][c], matrix[c][r] = matrix[c][r], matrix[r][c]

        for r in range(n):
            matrix[r].reverse()
```