Rotate ImageMedium

Rotate Image

Medium 17.2k73% acceptance

ArrayMatrixMath

You are given an n × n 2D matrix representing an image. Rotate the image 90 degrees clockwise.

Do the rotation in place — modify matrix directly without allocating another n × n grid — and return it.

Example 1

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

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

The top row 1,2,3 becomes the right column.

Example 2

Input: matrix = [[1,2],[3,4]]

Output: [[3,1],[4,2]]

Example 3

Input: matrix = [[5]]

Output: [[5]]

Constraints

Asked atAmazonMicrosoftAppleGoogle

JavaScript

⌘↵ to run

Loading editor…

Case 1

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

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

Case 2

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

expected: [[3,1],[4,2]]

Case 3

[[5]]

expected: [[5]]

Case 4

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

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

Case 5

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

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

Case 6

[[0,-1],[-2,-3]]

expected: [[-2,0],[-3,-1]]