# Leetcode 48 - Rotate image

Note:

• Use an array [prev, cur] to contain both new and old values.
• Be careful with boundaries, like we should use row - 1 - i instead of row - i.

Question:

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. DO NOT allocate another 2D matrix and do the rotation.

Example:

Code: