largest_number_from_given_digits

number = input()
list_number = []

for digit in number:
    list_number.append(int(digit))
while len(list_number) != 0:
    for i in range(len(list_number)-1, -1, -1):
        if list_number[i] == max(list_number):
            print(list_number[i], end="")
            list_number.pop(i)
            if len(list_number) == 0:
                break