Digit Game

def num_operations(a, b):
    max_num = 0
    if a + b > a * b:
        max_num = a + b
    else:
        max_num = a * b

    return max_num


number = [int(n) for n in input()]
biggest_number = 0

for num in number:
    temp = number.copy()
    temp.remove(num)

    temp_max = num_operations(temp[0], temp[1])

    if biggest_number < num_operations(num, temp_max):
        biggest_number = num_operations(num, temp_max)



print(biggest_number)