class Solution {
    public int[][] flipAndInvertImage(int[][] A) {
        // reverse
        for( int i = 0; i < A.length; i++)
        {
            for( int j = 0; i < A[i].length / 2; i++)
            {
                int len = A[i].length;
                int tmp = A[i][j];
                A[i][j] = A[i][len - j - 1];
                A[i][len - j - 1] = tmp;
            }
        }
        // invert
        System.out.println("invert");
        for( int i = 0; i < A.length; i++)
        {
            for( int j = 0; j < A[i].length; j++)
            {
                A[i][j] ^= 1;
            }
        }
        return A;
    }
}