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?

 

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-i-1;j++){
                int temp=matrix[i][j];
                matrix[i][j]=matrix[n-j-1][i];
                matrix[n-j-1][i]=matrix[n-i-1][n-j-1];
                matrix[n-i-1][n-j-1]=matrix[j][n-i-1];
                matrix[j][n-i-1]=temp;
            }
        }
    }
};