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?

void rotate(vector
     
      
       >& matrix) {    int n = matrix.size(), i, j, k, t, x, y, tx;    for(i = 0; i <= n>>1; i++)    {        for(j = i; j < n-1-i; j++)        {            t = matrix[i][j];            x = i; y = j;            for(k = 0; k < 3; k++)            {                matrix[x][y] = matrix[n-1-y][x];                tx = x;                x = n-1-y;                y = tx;            }            matrix[x][y] = t;        }    }}