LeetCode 48 - Rotate Image

Rotate Image

You are given an n x n 2D matrix representing an image.

Rotate the image by 90 degrees (clockwise).

Follow up:
Could you do this in-place?

My Code

class Solution {public:    void rotate(vector<vector<int> >& matrix) {        int n = matrix.size();        for (int i = 0; i < n / 2; i++)            for (int j = i; j < n - 1 - i; j++)            {                int tmp = matrix[n-1-j][i];                matrix[n-1-j][i] = matrix[n-1-i][n-1-j];                matrix[n-1-i][n-1-j] = matrix[j][n-1-i];                matrix[j][n-1-i] = matrix[i][j];                matrix[i][j] = tmp;            }        return;    }};

Runtime: 4 ms