def main():
    max_num = int(input())
    max_list = list(str(max_num))
    for i in range(len(max_list) - 1):
        for j in range(i + 1, len(max_list)):
            tmp = change(max_list, i, j)
            if tmp > max_num:
                max_num = tmp
            re_change(max_list, i, j)
    print(max_num)


def change(array, loop_i, loop_j):
    tmp = ""
    array[loop_i], array[loop_j] = array[loop_j], array[loop_i]
    for i in range(len(array)):
        tmp += array[i]
    return int(tmp)


def re_change(array, loop_i, loop_j):
    array[loop_j], array[loop_i] = array[loop_i], array[loop_j]


main()