for (int i = 0; i < grid.length; i++) {
            char[] charArr = grid[i].toCharArray();
            Arrays.sort(charArr);
            grid[i] = new String(charArr);
        }
        for (int i = 0; i < grid[0].length(); i++) {
            for (int j = 0; j < grid.length - 1; j++) {
                if (grid[j].charAt(i) > grid[j + 1].charAt(i)) {
                    return "NO";
                }
            }
        }
        return "YES";