// 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?

public class Solution {

public void rotate(int[][] matrix) {

for(int i = 0; i < matrix.length; i++) {

for(int j = 0; j < i; j++) {

int temp = matrix[i][j];

matrix[i][j] = matrix[j][i];

matrix[j][i] = temp;

}

}

for(int i = 0; i < matrix.length; i++) {

for(int j = 0; j < matrix[0].length / 2; j++) {

int temp = matrix[i][j];

matrix[i][j] = matrix[i][matrix[0].length - 1 - j];

matrix[i][matrix[0].length - 1 - j] = temp;

}

}

}

}