48. 旋转图像

class Solution {
    public void rotate(int[][] matrix) {
        int n = matrix.length;
        //水平翻转
        for (int i = 0; i < n / 2; i++) {
            for (int j = 0; j < n; j++) {
                int t = matrix[i][j];
                matrix[i][j] = matrix[n - i - 1][j];
                matrix[n - i - 1][j] = t;
            }
        }
        //主对角线翻转
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < i; j++) {
                int t = matrix[i][j];
                matrix[i][j] = matrix[j][i];
                matrix[j][i] = t;
            }
        }
    }
}